| <!DOCTYPE html><html lang="en"><head><meta charSet="utf-8"/><meta http-equiv="X-UA-Compatible" content="IE=edge"/><title>SQL · Apache Druid</title><meta name="viewport" content="width=device-width"/><link rel="canonical" href="https://druid.apache.org/docs/0.16.1-incubating/querying/sql.html"/><meta name="generator" content="Docusaurus"/><meta name="description" content="<!--"/><meta name="docsearch:language" content="en"/><meta name="docsearch:version" content="../../incubator-druid-website-src/" /><meta property="og:title" content="SQL · Apache Druid"/><meta property="og:type" content="website"/><meta property="og:url" content="https://druid.apache.org/index.html"/><meta property="og:description" content="<!--"/><meta property="og:image" content="https://druid.apache.org/img/druid_nav.png"/><meta name="twitter:card" content="summary"/><meta name="twitter:image" content="https://druid.apache.org/img/druid_nav.png"/><link rel="shortcut icon" href="/img/favicon.png"/><link rel="stylesheet" href="https://cdn.jsdelivr.net/docsearch.js/1/docsearch.min.css"/><link rel="stylesheet" href="//cdnjs.cloudflare.com/ajax/libs/highlight.js/9.12.0/styles/default.min.css"/><script async="" src="https://www.googletagmanager.com/gtag/js?id=UA-131010415-1"></script><script> |
| window.dataLayer = window.dataLayer || []; |
| function gtag(){dataLayer.push(arguments); } |
| gtag('js', new Date()); |
| gtag('config', 'UA-131010415-1'); |
| </script><link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.7.2/css/all.css"/><link rel="stylesheet" href="/css/code-block-buttons.css"/><script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/clipboard.js/2.0.4/clipboard.min.js"></script><script type="text/javascript" src="/js/code-block-buttons.js"></script><script src="/js/scrollSpy.js"></script><link rel="stylesheet" href="/css/main.css"/><script src="/js/codetabs.js"></script></head><body class="sideNavVisible separateOnPageNav"><div class="fixedHeaderContainer"><div class="headerWrapper wrapper"><header><a href="/"><img class="logo" src="/img/druid_nav.png" alt="Apache Druid"/></a><div class="navigationWrapper navigationSlider"><nav class="slidingNav"><ul class="nav-site nav-site-internal"><li class=""><a href="/technology" target="_self">Technology</a></li><li class=""><a href="/use-cases" target="_self">Use Cases</a></li><li class=""><a href="/druid-powered" target="_self">Powered By</a></li><li class="siteNavGroupActive"><a href="/docs/0.16.1-incubating/design/index.html" target="_self">Docs</a></li><li class=""><a href="/community/" target="_self">Community</a></li><li class=""><a href="https://www.apache.org" target="_self">Apache</a></li><li class=""><a href="/downloads.html" target="_self">Download</a></li><li class="navSearchWrapper reactNavSearchWrapper"><input type="text" id="search_input_react" placeholder="Search" title="Search"/></li></ul></nav></div></header></div></div><div class="navPusher"><div class="docMainWrapper wrapper"><div class="docsNavContainer" id="docsNav"><nav class="toc"><div class="toggleNav"><section class="navWrapper wrapper"><div class="navBreadcrumb wrapper"><div class="navToggle" id="navToggler"><div class="hamburger-menu"><div class="line1"></div><div class="line2"></div><div class="line3"></div></div></div><h2><i>›</i><span>Querying</span></h2><div class="tocToggler" id="tocToggler"><i class="icon-toc"></i></div></div><div class="navGroups"><div class="navGroup"><h3 class="navGroupCategoryTitle collapsible">Getting started<span class="arrow"><svg width="24" height="24" viewBox="0 0 24 24"><path fill="#565656" d="M7.41 15.41L12 10.83l4.59 4.58L18 14l-6-6-6 6z"></path><path d="M0 0h24v24H0z" fill="none"></path></svg></span></h3><ul class="hide"><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/design/index.html">Introduction to Apache Druid</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/tutorials/index.html">Quickstart</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/single-server.html">Single server deployment</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/tutorials/cluster.html">Clustered deployment</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle collapsible">Tutorials<span class="arrow"><svg width="24" height="24" viewBox="0 0 24 24"><path fill="#565656" d="M7.41 15.41L12 10.83l4.59 4.58L18 14l-6-6-6 6z"></path><path d="M0 0h24v24H0z" fill="none"></path></svg></span></h3><ul class="hide"><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/tutorials/tutorial-batch.html">Loading files natively</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/tutorials/tutorial-kafka.html">Load from Apache Kafka</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/tutorials/tutorial-batch-hadoop.html">Load from Apache Hadoop</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/tutorials/tutorial-query.html">Querying data</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/tutorials/tutorial-rollup.html">Roll-up</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/tutorials/tutorial-retention.html">Configuring data retention</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/tutorials/tutorial-update-data.html">Updating existing data</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/tutorials/tutorial-compaction.html">Compacting segments</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/tutorials/tutorial-delete-data.html">Deleting data</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/tutorials/tutorial-ingestion-spec.html">Writing an ingestion spec</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/tutorials/tutorial-transform-spec.html">Transforming input data</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/tutorials/tutorial-kerberos-hadoop.html">Kerberized HDFS deep storage</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle collapsible">Design<span class="arrow"><svg width="24" height="24" viewBox="0 0 24 24"><path fill="#565656" d="M7.41 15.41L12 10.83l4.59 4.58L18 14l-6-6-6 6z"></path><path d="M0 0h24v24H0z" fill="none"></path></svg></span></h3><ul class="hide"><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/design/architecture.html">Design</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/design/segments.html">Segments</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/design/processes.html">Processes and servers</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/dependencies/deep-storage.html">Deep storage</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/dependencies/metadata-storage.html">Metadata storage</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/dependencies/zookeeper.html">ZooKeeper</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle collapsible">Data ingestion<span class="arrow"><svg width="24" height="24" viewBox="0 0 24 24"><path fill="#565656" d="M7.41 15.41L12 10.83l4.59 4.58L18 14l-6-6-6 6z"></path><path d="M0 0h24v24H0z" fill="none"></path></svg></span></h3><ul class="hide"><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/ingestion/index.html">Ingestion</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/ingestion/data-formats.html">Data formats</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/ingestion/schema-design.html">Schema design tips</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/ingestion/data-management.html">Data management</a></li><div class="navGroup subNavGroup"><h4 class="navGroupSubcategoryTitle">Stream ingestion</h4><ul><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/kafka-ingestion.html">Apache Kafka</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/kinesis-ingestion.html">Amazon Kinesis</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/ingestion/tranquility.html">Tranquility</a></li></ul></div><div class="navGroup subNavGroup"><h4 class="navGroupSubcategoryTitle">Batch ingestion</h4><ul><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/ingestion/native-batch.html">Native batch</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/ingestion/hadoop.html">Hadoop-based</a></li></ul></div><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/ingestion/tasks.html">Task reference</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/ingestion/faq.html">Troubleshooting FAQ</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle collapsible">Querying<span class="arrow"><svg width="24" height="24" viewBox="0 0 24 24"><path fill="#565656" d="M7.41 15.41L12 10.83l4.59 4.58L18 14l-6-6-6 6z"></path><path d="M0 0h24v24H0z" fill="none"></path></svg></span></h3><ul class="hide"><li class="navListItem navListItemActive"><a class="navItem" href="/docs/0.16.1-incubating/querying/sql.html">Druid SQL</a></li><div class="navGroup subNavGroup"><h4 class="navGroupSubcategoryTitle">Native query types</h4><ul><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/querying.html">Making native queries</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/timeseriesquery.html">Timeseries</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/topnquery.html">TopN</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/groupbyquery.html">GroupBy</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/scan-query.html">Scan</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/timeboundaryquery.html">TimeBoundary</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/segmentmetadataquery.html">SegmentMetadata</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/datasourcemetadataquery.html">DatasourceMetadata</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/searchquery.html">Search</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/select-query.html">Select</a></li></ul></div><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/multi-value-dimensions.html">Multi-value dimensions</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/lookups.html">Lookups</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/joins.html">Joins</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/multitenancy.html">Multitenancy considerations</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/caching.html">Query caching</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/geo.html">Spatial filters</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle collapsible">Configuration<span class="arrow"><svg width="24" height="24" viewBox="0 0 24 24"><path fill="#565656" d="M7.41 15.41L12 10.83l4.59 4.58L18 14l-6-6-6 6z"></path><path d="M0 0h24v24H0z" fill="none"></path></svg></span></h3><ul class="hide"><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/configuration/index.html">Configuration reference</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions.html">Extensions</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/configuration/logging.html">Logging</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle collapsible">Operations<span class="arrow"><svg width="24" height="24" viewBox="0 0 24 24"><path fill="#565656" d="M7.41 15.41L12 10.83l4.59 4.58L18 14l-6-6-6 6z"></path><path d="M0 0h24v24H0z" fill="none"></path></svg></span></h3><ul class="hide"><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/management-uis.html">Management UIs</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/basic-cluster-tuning.html">Basic cluster tuning</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/api-reference.html">API reference</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/high-availability.html">High availability</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/rolling-updates.html">Rolling updates</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/rule-configuration.html">Retaining or automatically dropping data</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/metrics.html">Metrics</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/alerts.html">Alerts</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/other-hadoop.html">Working with different versions of Apache Hadoop</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/http-compression.html">HTTP compression</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/recommendations.html">Recommendations</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/tls-support.html">TLS support</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/password-provider.html">Password providers</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/dump-segment.html">dump-segment tool</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/reset-cluster.html">reset-cluster tool</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/insert-segment-to-db.html">insert-segment-to-db tool</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/pull-deps.html">pull-deps tool</a></li><div class="navGroup subNavGroup"><h4 class="navGroupSubcategoryTitle">Misc</h4><ul><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/deep-storage-migration.html">Deep storage migration</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/druid-console.html">Web console</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/export-metadata.html">Export Metadata Tool</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/getting-started.html">Getting started with Apache Druid</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/metadata-migration.html">Metadata Migration</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/segment-optimization.html">Segment Size Optimization</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/operations/use_sbt_to_build_fat_jar.html">Content for build.sbt</a></li></ul></div></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle collapsible">Development<span class="arrow"><svg width="24" height="24" viewBox="0 0 24 24"><path fill="#565656" d="M7.41 15.41L12 10.83l4.59 4.58L18 14l-6-6-6 6z"></path><path d="M0 0h24v24H0z" fill="none"></path></svg></span></h3><ul class="hide"><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/overview.html">Developing on Druid</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/modules.html">Creating extensions</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/javascript.html">JavaScript functionality</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/build.html">Build from source</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/versioning.html">Versioning</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/experimental.html">Experimental features</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle collapsible">Misc<span class="arrow"><svg width="24" height="24" viewBox="0 0 24 24"><path fill="#565656" d="M7.41 15.41L12 10.83l4.59 4.58L18 14l-6-6-6 6z"></path><path d="M0 0h24v24H0z" fill="none"></path></svg></span></h3><ul class="hide"><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/misc/math-expr.html">Expressions</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/misc/papers-and-talks.html">Papers</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle collapsible">Hidden<span class="arrow"><svg width="24" height="24" viewBox="0 0 24 24"><path fill="#565656" d="M7.41 15.41L12 10.83l4.59 4.58L18 14l-6-6-6 6z"></path><path d="M0 0h24v24H0z" fill="none"></path></svg></span></h3><ul class="hide"><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/comparisons/druid-vs-elasticsearch.html">Apache Druid vs Elasticsearch</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/comparisons/druid-vs-key-value.html">Apache Druid vs. Key/Value Stores (HBase/Cassandra/OpenTSDB)</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/comparisons/druid-vs-kudu.html">Apache Druid vs Kudu</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/comparisons/druid-vs-redshift.html">Apache Druid vs Redshift</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/comparisons/druid-vs-spark.html">Apache Druid vs Spark</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/comparisons/druid-vs-sql-on-hadoop.html">Apache Druid vs SQL-on-Hadoop</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/design/auth.html">Authentication and Authorization</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/design/broker.html">Broker</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/design/coordinator.html">Coordinator Process</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/design/historical.html">Historical Process</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/design/indexer.html">Indexer Process</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/design/indexing-service.html">Indexing Service</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/design/middlemanager.html">MiddleManager Process</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/design/overlord.html">Overlord Process</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/design/router.html">Router Process</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/design/peons.html">Peons</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/approximate-histograms.html">Approximate Histogram aggregators</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/avro.html">Apache Avro</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/bloom-filter.html">Bloom Filter</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/datasketches-extension.html">DataSketches extension</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/datasketches-hll.html">DataSketches HLL Sketch module</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/datasketches-quantiles.html">DataSketches Quantiles Sketch module</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/datasketches-theta.html">DataSketches Theta Sketch module</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/datasketches-tuple.html">DataSketches Tuple Sketch module</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/druid-basic-security.html">Basic Security</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/druid-kerberos.html">Kerberos</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/druid-lookups.html">Cached Lookup Module</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/google.html">Google Cloud Storage</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/hdfs.html">HDFS</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/kafka-extraction-namespace.html">Apache Kafka Lookups</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/lookups-cached-global.html">Globally Cached Lookups</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/mysql.html">MySQL Metadata Store</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/orc.html">ORC Extension</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/parquet.html">Apache Parquet Extension</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/postgresql.html">PostgreSQL Metadata Store</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/protobuf.html">Protobuf</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/s3.html">S3-compatible</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/simple-client-sslcontext.html">Simple SSLContext Provider Module</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/stats.html">Stats aggregator</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-core/test-stats.html">Test Stats Aggregators</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/ambari-metrics-emitter.html">Ambari Metrics Emitter</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/azure.html">Microsoft Azure</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/cassandra.html">Apache Cassandra</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/cloudfiles.html">Rackspace Cloud Files</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/distinctcount.html">DistinctCount Aggregator</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/graphite.html">Graphite Emitter</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/aggregations.html">Aggregations</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/datasource.html">Datasources</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/dimensionspecs.html">Transforming Dimension Values</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/filters.html">Query Filters</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/granularities.html">Aggregation Granularity</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/having.html">Filter groupBy query results</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/hll-old.html">Cardinality/HyperUnique aggregators</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/limitspec.html">Sort groupBy query results</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/post-aggregations.html">Post-Aggregations</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/query-context.html">Query context</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/searchqueryspec.html">Refining search queries</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/sorting-orders.html">Sorting Orders</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/topnmetricspec.html">TopNMetricSpec</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/querying/virtual-columns.html">Virtual Columns</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/influx.html">InfluxDB Line Protocol Parser</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/influxdb-emitter.html">InfluxDB Emitter</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/kafka-emitter.html">Kafka Emitter</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/materialized-view.html">Materialized View</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/momentsketch-quantiles.html">Moment Sketches for Approximate Quantiles module</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/moving-average-query.html">development/extensions-contrib/moving-average-query</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/opentsdb-emitter.html">OpenTSDB Emitter</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/redis-cache.html">Druid Redis Cache</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/sqlserver.html">Microsoft SQLServer</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/statsd.html">StatsD Emitter</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/tdigestsketch-quantiles.html">T-Digest Quantiles Sketch module</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/thrift.html">Thrift</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/development/extensions-contrib/time-min-max.html">Timestamp Min/Max aggregators</a></li><li class="navListItem"><a class="navItem" href="/docs/0.16.1-incubating/ingestion/standalone-realtime.html">Realtime Process</a></li></ul></div></div></section></div><script> |
| var coll = document.getElementsByClassName('collapsible'); |
| var checkActiveCategory = true; |
| for (var i = 0; i < coll.length; i++) { |
| var links = coll[i].nextElementSibling.getElementsByTagName('*'); |
| if (checkActiveCategory){ |
| for (var j = 0; j < links.length; j++) { |
| if (links[j].classList.contains('navListItemActive')){ |
| coll[i].nextElementSibling.classList.toggle('hide'); |
| coll[i].childNodes[1].classList.toggle('rotate'); |
| checkActiveCategory = false; |
| break; |
| } |
| } |
| } |
| |
| coll[i].addEventListener('click', function() { |
| var arrow = this.childNodes[1]; |
| arrow.classList.toggle('rotate'); |
| var content = this.nextElementSibling; |
| content.classList.toggle('hide'); |
| }); |
| } |
| |
| document.addEventListener('DOMContentLoaded', function() { |
| createToggler('#navToggler', '#docsNav', 'docsSliderActive'); |
| createToggler('#tocToggler', 'body', 'tocActive'); |
| |
| var headings = document.querySelector('.toc-headings'); |
| headings && headings.addEventListener('click', function(event) { |
| var el = event.target; |
| while(el !== headings){ |
| if (el.tagName === 'A') { |
| document.body.classList.remove('tocActive'); |
| break; |
| } else{ |
| el = el.parentNode; |
| } |
| } |
| }, false); |
| |
| function createToggler(togglerSelector, targetSelector, className) { |
| var toggler = document.querySelector(togglerSelector); |
| var target = document.querySelector(targetSelector); |
| |
| if (!toggler) { |
| return; |
| } |
| |
| toggler.onclick = function(event) { |
| event.preventDefault(); |
| |
| target.classList.toggle(className); |
| }; |
| } |
| }); |
| </script></nav></div><div class="container mainContainer"><div class="wrapper"><div class="post"><header class="postHeader"><a class="edit-page-link button" href="https://github.com/apache/incubator-druid/edit/master/docs/querying/sql.md" target="_blank" rel="noreferrer noopener">Edit</a><h1 class="postHeaderTitle">SQL</h1></header><article><div><span><!-- |
| ~ Licensed to the Apache Software Foundation (ASF) under one |
| ~ or more contributor license agreements. See the NOTICE file |
| ~ distributed with this work for additional information |
| ~ regarding copyright ownership. The ASF licenses this file |
| ~ to you under the Apache License, Version 2.0 (the |
| ~ "License"); you may not use this file except in compliance |
| ~ with the License. You may obtain a copy of the License at |
| ~ |
| ~ http://www.apache.org/licenses/LICENSE-2.0 |
| ~ |
| ~ Unless required by applicable law or agreed to in writing, |
| ~ software distributed under the License is distributed on an |
| ~ "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| ~ KIND, either express or implied. See the License for the |
| ~ specific language governing permissions and limitations |
| ~ under the License. |
| --> |
| <!-- |
| The format of the tables that describe the functions and operators |
| should not be changed without updating the script create-sql-function-doc |
| in web-console/script/create-sql-function-doc, because the script detects |
| patterns in this markdown file and parse it to TypeScript file for web console |
| --> |
| <blockquote> |
| <p>Apache Druid (incubating) supports two query languages: Druid SQL and <a href="/docs/0.16.1-incubating/querying/querying.html">native queries</a>, which |
| SQL queries are planned into, and which end users can also issue directly. This document describes the SQL language.</p> |
| </blockquote> |
| <p>Druid SQL is a built-in SQL layer and an alternative to Druid's native JSON-based query language, and is powered by a |
| parser and planner based on <a href="https://calcite.apache.org/">Apache Calcite</a>. Druid SQL translates SQL into native Druid |
| queries on the query Broker (the first process you query), which are then passed down to data processes as native Druid |
| queries. Other than the (slight) overhead of translating SQL on the Broker, there isn't an additional performance |
| penalty versus native queries.</p> |
| <h2><a class="anchor" aria-hidden="true" id="query-syntax"></a><a href="#query-syntax" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Query syntax</h2> |
| <p>Each Druid datasource appears as a table in the "druid" schema. This is also the default schema, so Druid datasources |
| can be referenced as either <code>druid.dataSourceName</code> or simply <code>dataSourceName</code>.</p> |
| <p>Identifiers like datasource and column names can optionally be quoted using double quotes. To escape a double quote |
| inside an identifier, use another double quote, like <code>"My ""very own"" identifier"</code>. All identifiers are case-sensitive |
| and no implicit case conversions are performed.</p> |
| <p>Literal strings should be quoted with single quotes, like <code>'foo'</code>. Literal strings with Unicode escapes can be written |
| like <code>U&'fo\00F6'</code>, where character codes in hex are prefixed by a backslash. Literal numbers can be written in forms |
| like <code>100</code> (denoting an integer), <code>100.0</code> (denoting a floating point value), or <code>1.0e5</code> (scientific notation). Literal |
| timestamps can be written like <code>TIMESTAMP '2000-01-01 00:00:00'</code>. Literal intervals, used for time arithmetic, can be |
| written like <code>INTERVAL '1' HOUR</code>, <code>INTERVAL '1 02:03' DAY TO MINUTE</code>, <code>INTERVAL '1-2' YEAR TO MONTH</code>, and so on.</p> |
| <p>Druid SQL supports SELECT queries with the following structure:</p> |
| <pre><code class="hljs">[ <span class="hljs-keyword">EXPLAIN</span> PLAN <span class="hljs-keyword">FOR</span> ] |
| [ <span class="hljs-keyword">WITH</span> tableName [ ( column1, column2, ... ) ] <span class="hljs-keyword">AS</span> ( <span class="hljs-keyword">query</span> ) ] |
| <span class="hljs-keyword">SELECT</span> [ <span class="hljs-keyword">ALL</span> | <span class="hljs-keyword">DISTINCT</span> ] { * | exprs } |
| <span class="hljs-keyword">FROM</span> <span class="hljs-keyword">table</span> |
| [ <span class="hljs-keyword">WHERE</span> expr ] |
| [ <span class="hljs-keyword">GROUP</span> <span class="hljs-keyword">BY</span> exprs ] |
| [ <span class="hljs-keyword">HAVING</span> expr ] |
| [ <span class="hljs-keyword">ORDER</span> <span class="hljs-keyword">BY</span> expr [ <span class="hljs-keyword">ASC</span> | <span class="hljs-keyword">DESC</span> ], expr [ <span class="hljs-keyword">ASC</span> | <span class="hljs-keyword">DESC</span> ], ... ] |
| [ <span class="hljs-keyword">LIMIT</span> <span class="hljs-keyword">limit</span> ] |
| [ <span class="hljs-keyword">UNION</span> <span class="hljs-keyword">ALL</span> <another <span class="hljs-keyword">query</span>> ] |
| </code></pre> |
| <p>The FROM clause refers to either a Druid datasource, like <code>druid.foo</code>, an <a href="#metadata-tables">INFORMATION_SCHEMA table</a>, a |
| subquery, or a common-table-expression provided in the WITH clause. If the FROM clause references a subquery or a |
| common-table-expression, and both levels of queries are aggregations and they cannot be combined into a single level of |
| aggregation, the overall query will be executed as a <a href="groupbyquery.html#nested-groupbys">nested GroupBy</a>.</p> |
| <p>The WHERE clause refers to columns in the FROM table, and will be translated to <a href="filters.html">native filters</a>. The |
| WHERE clause can also reference a subquery, like <code>WHERE col1 IN (SELECT foo FROM ...)</code>. Queries like this are executed |
| as <a href="#query-execution">semi-joins</a>, described below.</p> |
| <p>The GROUP BY clause refers to columns in the FROM table. Using GROUP BY, DISTINCT, or any aggregation functions will |
| trigger an aggregation query using one of Druid's <a href="#query-execution">three native aggregation query types</a>. GROUP BY |
| can refer to an expression or a select clause ordinal position (like <code>GROUP BY 2</code> to group by the second selected |
| column).</p> |
| <p>The HAVING clause refers to columns that are present after execution of GROUP BY. It can be used to filter on either |
| grouping expressions or aggregated values. It can only be used together with GROUP BY.</p> |
| <p>The ORDER BY clause refers to columns that are present after execution of GROUP BY. It can be used to order the results |
| based on either grouping expressions or aggregated values. ORDER BY can refer to an expression or a select clause |
| ordinal position (like <code>ORDER BY 2</code> to order by the second selected column). For non-aggregation queries, ORDER BY |
| can only order by the <code>__time</code> column. For aggregation queries, ORDER BY can order by any column.</p> |
| <p>The LIMIT clause can be used to limit the number of rows returned. It can be used with any query type. It is pushed down |
| to data processes for queries that run with the native TopN query type, but not the native GroupBy query type. Future |
| versions of Druid will support pushing down limits using the native GroupBy query type as well. If you notice that |
| adding a limit doesn't change performance very much, then it's likely that Druid didn't push down the limit for your |
| query.</p> |
| <p>The "UNION ALL" operator can be used to fuse multiple queries together. Their results will be concatenated, and each |
| query will run separately, back to back (not in parallel). Druid does not currently support "UNION" without "ALL".</p> |
| <p>Add "EXPLAIN PLAN FOR" to the beginning of any query to see how it would be run as a native Druid query. In this case, |
| the query will not actually be executed.</p> |
| <h2><a class="anchor" aria-hidden="true" id="data-types-and-casts"></a><a href="#data-types-and-casts" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Data types and casts</h2> |
| <p>Druid natively supports five basic column types: "long" (64 bit signed int), "float" (32 bit float), "double" (64 bit |
| float) "string" (UTF-8 encoded strings and string arrays), and "complex" (catch-all for more exotic data types like |
| hyperUnique and approxHistogram columns).</p> |
| <p>Timestamps (including the <code>__time</code> column) are treated by Druid as longs, with the value being the number of |
| milliseconds since 1970-01-01 00:00:00 UTC, not counting leap seconds. Therefore, timestamps in Druid do not carry any |
| timezone information, but only carry information about the exact moment in time they represent. See the |
| <a href="#time-functions">Time functions</a> section for more information about timestamp handling.</p> |
| <p>Druid generally treats NULLs and empty strings interchangeably, rather than according to the SQL standard. As such, |
| Druid SQL only has partial support for NULLs. For example, the expressions <code>col IS NULL</code> and <code>col = ''</code> are equivalent, |
| and both will evaluate to true if <code>col</code> contains an empty string. Similarly, the expression <code>COALESCE(col1, col2)</code> will |
| return <code>col2</code> if <code>col1</code> is an empty string. While the <code>COUNT(*)</code> aggregator counts all rows, the <code>COUNT(expr)</code> |
| aggregator will count the number of rows where expr is neither null nor the empty string. String columns in Druid are |
| NULLable. Numeric columns are NOT NULL; if you query a numeric column that is not present in all segments of your Druid |
| datasource, then it will be treated as zero for rows from those segments.</p> |
| <p>For mathematical operations, Druid SQL will use integer math if all operands involved in an expression are integers. |
| Otherwise, Druid will switch to floating point math. You can force this to happen by casting one of your operands |
| to FLOAT. At runtime, Druid may widen 32-bit floats to 64-bit for certain operators, like SUM aggregators.</p> |
| <p>Druid <a href="multi-value-dimensions.html">multi-value string dimensions</a> will appear in the table schema as <code>VARCHAR</code> typed, |
| and may be interacted with in expressions as such. Additionally, they can be treated as <code>ARRAY</code> 'like', via a handful of |
| special multi-value operators. Expressions against multi-value string dimensions will apply the expression to all values |
| of the row, however the caveat is that aggregations on these multi-value string columns will observe the native Druid |
| multi-value aggregation behavior, which is equivalent to the <code>UNNEST</code> function available in many dialects. |
| Refer to the documentation on <a href="multi-value-dimensions.html">multi-value string dimensions</a> and |
| <a href="../misc/math-expr.html">Druid expressions documentation</a> for additional details.</p> |
| <p>The following table describes how SQL types map onto Druid types during query runtime. Casts between two SQL types |
| that have the same Druid runtime type will have no effect, other than exceptions noted in the table. Casts between two |
| SQL types that have different Druid runtime types will generate a runtime cast in Druid. If a value cannot be properly |
| cast to another value, as in <code>CAST('foo' AS BIGINT)</code>, the runtime will substitute a default value. NULL values cast |
| to non-nullable types will also be substituted with a default value (for example, nulls cast to numbers will be |
| converted to zeroes).</p> |
| <table> |
| <thead> |
| <tr><th>SQL type</th><th>Druid runtime type</th><th>Default value</th><th>Notes</th></tr> |
| </thead> |
| <tbody> |
| <tr><td>CHAR</td><td>STRING</td><td><code>''</code></td><td></td></tr> |
| <tr><td>VARCHAR</td><td>STRING</td><td><code>''</code></td><td>Druid STRING columns are reported as VARCHAR</td></tr> |
| <tr><td>DECIMAL</td><td>DOUBLE</td><td><code>0.0</code></td><td>DECIMAL uses floating point, not fixed point math</td></tr> |
| <tr><td>FLOAT</td><td>FLOAT</td><td><code>0.0</code></td><td>Druid FLOAT columns are reported as FLOAT</td></tr> |
| <tr><td>REAL</td><td>DOUBLE</td><td><code>0.0</code></td><td></td></tr> |
| <tr><td>DOUBLE</td><td>DOUBLE</td><td><code>0.0</code></td><td>Druid DOUBLE columns are reported as DOUBLE</td></tr> |
| <tr><td>BOOLEAN</td><td>LONG</td><td><code>false</code></td><td></td></tr> |
| <tr><td>TINYINT</td><td>LONG</td><td><code>0</code></td><td></td></tr> |
| <tr><td>SMALLINT</td><td>LONG</td><td><code>0</code></td><td></td></tr> |
| <tr><td>INTEGER</td><td>LONG</td><td><code>0</code></td><td></td></tr> |
| <tr><td>BIGINT</td><td>LONG</td><td><code>0</code></td><td>Druid LONG columns (except <code>__time</code>) are reported as BIGINT</td></tr> |
| <tr><td>TIMESTAMP</td><td>LONG</td><td><code>0</code>, meaning 1970-01-01 00:00:00 UTC</td><td>Druid's <code>__time</code> column is reported as TIMESTAMP. Casts between string and timestamp types assume standard SQL formatting, e.g. <code>2000-01-02 03:04:05</code>, <em>not</em> ISO8601 formatting. For handling other formats, use one of the <a href="#time-functions">time functions</a></td></tr> |
| <tr><td>DATE</td><td>LONG</td><td><code>0</code>, meaning 1970-01-01</td><td>Casting TIMESTAMP to DATE rounds down the timestamp to the nearest day. Casts between string and date types assume standard SQL formatting, e.g. <code>2000-01-02</code>. For handling other formats, use one of the <a href="#time-functions">time functions</a></td></tr> |
| <tr><td>OTHER</td><td>COMPLEX</td><td>none</td><td>May represent various Druid column types such as hyperUnique, approxHistogram, etc</td></tr> |
| </tbody> |
| </table> |
| <h2><a class="anchor" aria-hidden="true" id="built-in-functions"></a><a href="#built-in-functions" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Built-in functions</h2> |
| <h3><a class="anchor" aria-hidden="true" id="aggregation-functions"></a><a href="#aggregation-functions" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Aggregation functions</h3> |
| <p>Aggregation functions can appear in the SELECT clause of any query. Any aggregator can be filtered using syntax like |
| <code>AGG(expr) FILTER(WHERE whereExpr)</code>. Filtered aggregators will only aggregate rows that match their filter. It's |
| possible for two aggregators in the same SQL query to have different filters.</p> |
| <p>Only the COUNT aggregation can accept DISTINCT.</p> |
| <table> |
| <thead> |
| <tr><th>Function</th><th>Notes</th></tr> |
| </thead> |
| <tbody> |
| <tr><td><code>COUNT(*)</code></td><td>Counts the number of rows.</td></tr> |
| <tr><td><code>COUNT(DISTINCT expr)</code></td><td>Counts distinct values of expr, which can be string, numeric, or hyperUnique. By default this is approximate, using a variant of <a href="http://algo.inria.fr/flajolet/Publications/FlFuGaMe07.pdf">HyperLogLog</a>. To get exact counts set "useApproximateCountDistinct" to "false". If you do this, expr must be string or numeric, since exact counts are not possible using hyperUnique columns. See also <code>APPROX_COUNT_DISTINCT(expr)</code>. In exact mode, only one distinct count per query is permitted.</td></tr> |
| <tr><td><code>SUM(expr)</code></td><td>Sums numbers.</td></tr> |
| <tr><td><code>MIN(expr)</code></td><td>Takes the minimum of numbers.</td></tr> |
| <tr><td><code>MAX(expr)</code></td><td>Takes the maximum of numbers.</td></tr> |
| <tr><td><code>AVG(expr)</code></td><td>Averages numbers.</td></tr> |
| <tr><td><code>APPROX_COUNT_DISTINCT(expr)</code></td><td>Counts distinct values of expr, which can be a regular column or a hyperUnique column. This is always approximate, regardless of the value of "useApproximateCountDistinct". This uses Druid's built-in "cardinality" or "hyperUnique" aggregators. See also <code>COUNT(DISTINCT expr)</code>.</td></tr> |
| <tr><td><code>APPROX_COUNT_DISTINCT_DS_HLL(expr, [lgK, tgtHllType])</code></td><td>Counts distinct values of expr, which can be a regular column or an <a href="../development/extensions-core/datasketches-hll.html">HLL sketch</a> column. The <code>lgK</code> and <code>tgtHllType</code> parameters are described in the HLL sketch documentation. This is always approximate, regardless of the value of "useApproximateCountDistinct". See also <code>COUNT(DISTINCT expr)</code>. The <a href="../development/extensions-core/datasketches-extension.html">DataSketches extension</a> must be loaded to use this function.</td></tr> |
| <tr><td><code>APPROX_COUNT_DISTINCT_DS_THETA(expr, [size])</code></td><td>Counts distinct values of expr, which can be a regular column or a <a href="../development/extensions-core/datasketches-theta.html">Theta sketch</a> column. The <code>size</code> parameter is described in the Theta sketch documentation. This is always approximate, regardless of the value of "useApproximateCountDistinct". See also <code>COUNT(DISTINCT expr)</code>. The <a href="../development/extensions-core/datasketches-extension.html">DataSketches extension</a> must be loaded to use this function.</td></tr> |
| <tr><td><code>APPROX_QUANTILE(expr, probability, [resolution])</code></td><td>Computes approximate quantiles on numeric or <a href="../development/extensions-core/approximate-histograms.html#approximate-histogram-aggregator">approxHistogram</a> exprs. The "probability" should be between 0 and 1 (exclusive). The "resolution" is the number of centroids to use for the computation. Higher resolutions will give more precise results but also have higher overhead. If not provided, the default resolution is 50. The <a href="../development/extensions-core/approximate-histograms.html">approximate histogram extension</a> must be loaded to use this function.</td></tr> |
| <tr><td><code>APPROX_QUANTILE_DS(expr, probability, [k])</code></td><td>Computes approximate quantiles on numeric or <a href="../development/extensions-core/datasketches-quantiles.html">Quantiles sketch</a> exprs. The "probability" should be between 0 and 1 (exclusive). The <code>k</code> parameter is described in the Quantiles sketch documentation. The <a href="../development/extensions-core/datasketches-extension.html">DataSketches extension</a> must be loaded to use this function.</td></tr> |
| <tr><td><code>APPROX_QUANTILE_FIXED_BUCKETS(expr, probability, numBuckets, lowerLimit, upperLimit, [outlierHandlingMode])</code></td><td>Computes approximate quantiles on numeric or <a href="../development/extensions-core/approximate-histograms.html#fixed-buckets-histogram">fixed buckets histogram</a> exprs. The "probability" should be between 0 and 1 (exclusive). The <code>numBuckets</code>, <code>lowerLimit</code>, <code>upperLimit</code>, and <code>outlierHandlingMode</code> parameters are described in the fixed buckets histogram documentation. The <a href="../development/extensions-core/approximate-histograms.html">approximate histogram extension</a> must be loaded to use this function.</td></tr> |
| <tr><td><code>BLOOM_FILTER(expr, numEntries)</code></td><td>Computes a bloom filter from values produced by <code>expr</code>, with <code>numEntries</code> maximum number of distinct values before false positive rate increases. See <a href="../development/extensions-core/bloom-filter.html">bloom filter extension</a> documentation for additional details.</td></tr> |
| <tr><td><code>TDIGEST_QUANTILE(expr, quantileFraction, [compression])</code></td><td>Builds a T-Digest sketch on values produced by <code>expr</code> and returns the value for the quantile. Compression parameter (default value 100) determines the accuracy and size of the sketch. Higher compression means higher accuracy but more space to store sketches. See <a href="../development/extensions-contrib/tdigestsketch-quantiles.html">t-digest extension</a> documentation for additional details.</td></tr> |
| <tr><td><code>TDIGEST_GENERATE_SKETCH(expr, [compression])</code></td><td>Builds a T-Digest sketch on values produced by <code>expr</code>. Compression parameter (default value 100) determines the accuracy and size of the sketch Higher compression means higher accuracy but more space to store sketches. See <a href="../development/extensions-contrib/tdigestsketch-quantiles.html">t-digest extension</a> documentation for additional details.</td></tr> |
| <tr><td><code>VAR_POP(expr)</code></td><td>Computes variance population of <code>expr</code>. See <a href="../development/extensions-core/stats.html">stats extension</a> documentation for additional details.</td></tr> |
| <tr><td><code>VAR_SAMP(expr)</code></td><td>Computes variance sample of <code>expr</code>. See <a href="../development/extensions-core/stats.html">stats extension</a> documentation for additional details.</td></tr> |
| <tr><td><code>VARIANCE(expr)</code></td><td>Computes variance sample of <code>expr</code>. See <a href="../development/extensions-core/stats.html">stats extension</a> documentation for additional details.</td></tr> |
| <tr><td><code>STDDEV_POP(expr)</code></td><td>Computes standard deviation population of <code>expr</code>. See <a href="../development/extensions-core/stats.html">stats extension</a> documentation for additional details.</td></tr> |
| <tr><td><code>STDDEV_SAMP(expr)</code></td><td>Computes standard deviation sample of <code>expr</code>. See <a href="../development/extensions-core/stats.html">stats extension</a> documentation for additional details.</td></tr> |
| <tr><td><code>STDDEV(expr)</code></td><td>Computes standard deviation sample of <code>expr</code>. See <a href="../development/extensions-core/stats.html">stats extension</a> documentation for additional details.</td></tr> |
| </tbody> |
| </table> |
| <p>For advice on choosing approximate aggregation functions, check out our <a href="aggregations.html#approx">approximate aggregations documentation</a>.</p> |
| <h3><a class="anchor" aria-hidden="true" id="numeric-functions"></a><a href="#numeric-functions" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Numeric functions</h3> |
| <p>Numeric functions will return 64 bit integers or 64 bit floats, depending on their inputs.</p> |
| <table> |
| <thead> |
| <tr><th>Function</th><th>Notes</th></tr> |
| </thead> |
| <tbody> |
| <tr><td><code>ABS(expr)</code></td><td>Absolute value.</td></tr> |
| <tr><td><code>CEIL(expr)</code></td><td>Ceiling.</td></tr> |
| <tr><td><code>EXP(expr)</code></td><td>e to the power of expr.</td></tr> |
| <tr><td><code>FLOOR(expr)</code></td><td>Floor.</td></tr> |
| <tr><td><code>LN(expr)</code></td><td>Logarithm (base e).</td></tr> |
| <tr><td><code>LOG10(expr)</code></td><td>Logarithm (base 10).</td></tr> |
| <tr><td><code>POWER(expr, power)</code></td><td>expr to a power.</td></tr> |
| <tr><td><code>SQRT(expr)</code></td><td>Square root.</td></tr> |
| <tr><td><code>TRUNCATE(expr[, digits])</code></td><td>Truncate expr to a specific number of decimal digits. If digits is negative, then this truncates that many places to the left of the decimal point. Digits defaults to zero if not specified.</td></tr> |
| <tr><td><code>TRUNC(expr[, digits])</code></td><td>Synonym for <code>TRUNCATE</code>.</td></tr> |
| <tr><td><code>ROUND(expr[, digits])</code></td><td><code>ROUND(x, y)</code> would return the value of the x rounded to the y decimal places. While x can be an integer or floating-point number, y must be an integer. The type of the return value is specified by that of x. y defaults to 0 if omitted. When y is negative, x is rounded on the left side of the y decimal points.</td></tr> |
| <tr><td><code>x + y</code></td><td>Addition.</td></tr> |
| <tr><td><code>x - y</code></td><td>Subtraction.</td></tr> |
| <tr><td><code>x * y</code></td><td>Multiplication.</td></tr> |
| <tr><td><code>x / y</code></td><td>Division.</td></tr> |
| <tr><td><code>MOD(x, y)</code></td><td>Modulo (remainder of x divided by y).</td></tr> |
| <tr><td><code>SIN(expr)</code></td><td>Trigonometric sine of an angle expr.</td></tr> |
| <tr><td><code>COS(expr)</code></td><td>Trigonometric cosine of an angle expr.</td></tr> |
| <tr><td><code>TAN(expr)</code></td><td>Trigonometric tangent of an angle expr.</td></tr> |
| <tr><td><code>COT(expr)</code></td><td>Trigonometric cotangent of an angle expr.</td></tr> |
| <tr><td><code>ASIN(expr)</code></td><td>Arc sine of expr.</td></tr> |
| <tr><td><code>ACOS(expr)</code></td><td>Arc cosine of expr.</td></tr> |
| <tr><td><code>ATAN(expr)</code></td><td>Arc tangent of expr.</td></tr> |
| <tr><td><code>ATAN2(y, x)</code></td><td>Angle theta from the conversion of rectangular coordinates (x, y) to polar * coordinates (r, theta).</td></tr> |
| <tr><td><code>DEGREES(expr)</code></td><td>Converts an angle measured in radians to an approximately equivalent angle measured in degrees</td></tr> |
| <tr><td><code>RADIANS(expr)</code></td><td>Converts an angle measured in degrees to an approximately equivalent angle measured in radians</td></tr> |
| </tbody> |
| </table> |
| <h3><a class="anchor" aria-hidden="true" id="string-functions"></a><a href="#string-functions" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>String functions</h3> |
| <p>String functions accept strings, and return a type appropriate to the function.</p> |
| <table> |
| <thead> |
| <tr><th>Function</th><th>Notes</th></tr> |
| </thead> |
| <tbody> |
| <tr><td><code>x || y</code></td><td>Concat strings x and y.</td></tr> |
| <tr><td><code>CONCAT(expr, expr...)</code></td><td>Concats a list of expressions.</td></tr> |
| <tr><td><code>TEXTCAT(expr, expr)</code></td><td>Two argument version of CONCAT.</td></tr> |
| <tr><td><code>STRING_FORMAT(pattern[, args...])</code></td><td>Returns a string formatted in the manner of Java's <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html#format-java.lang.String-java.lang.Object...-">String.format</a>.</td></tr> |
| <tr><td><code>LENGTH(expr)</code></td><td>Length of expr in UTF-16 code units.</td></tr> |
| <tr><td><code>CHAR_LENGTH(expr)</code></td><td>Synonym for <code>LENGTH</code>.</td></tr> |
| <tr><td><code>CHARACTER_LENGTH(expr)</code></td><td>Synonym for <code>LENGTH</code>.</td></tr> |
| <tr><td><code>STRLEN(expr)</code></td><td>Synonym for <code>LENGTH</code>.</td></tr> |
| <tr><td><code>LOOKUP(expr, lookupName)</code></td><td>Look up expr in a registered <a href="lookups.html">query-time lookup table</a>.</td></tr> |
| <tr><td><code>LOWER(expr)</code></td><td>Returns expr in all lowercase.</td></tr> |
| <tr><td><code>PARSE_LONG(string[, radix])</code></td><td>Parses a string into a long (BIGINT) with the given radix, or 10 (decimal) if a radix is not provided.</td></tr> |
| <tr><td><code>POSITION(needle IN haystack [FROM fromIndex])</code></td><td>Returns the index of needle within haystack, with indexes starting from 1. The search will begin at fromIndex, or 1 if fromIndex is not specified. If the needle is not found, returns 0.</td></tr> |
| <tr><td><code>REGEXP_EXTRACT(expr, pattern, [index])</code></td><td>Apply regular expression pattern and extract a capture group, or null if there is no match. If index is unspecified or zero, returns the substring that matched the pattern.</td></tr> |
| <tr><td><code>REPLACE(expr, pattern, replacement)</code></td><td>Replaces pattern with replacement in expr, and returns the result.</td></tr> |
| <tr><td><code>STRPOS(haystack, needle)</code></td><td>Returns the index of needle within haystack, with indexes starting from 1. If the needle is not found, returns 0.</td></tr> |
| <tr><td><code>SUBSTRING(expr, index, [length])</code></td><td>Returns a substring of expr starting at index, with a max length, both measured in UTF-16 code units.</td></tr> |
| <tr><td><code>RIGHT(expr, [length])</code></td><td>Returns the rightmost length characters from expr.</td></tr> |
| <tr><td><code>LEFT(expr, [length])</code></td><td>Returns the leftmost length characters from expr.</td></tr> |
| <tr><td><code>SUBSTR(expr, index, [length])</code></td><td>Synonym for SUBSTRING.</td></tr> |
| <tr><td><code>TRIM([BOTH | LEADING | TRAILING] [<chars> FROM] expr)</code></td><td>Returns expr with characters removed from the leading, trailing, or both ends of "expr" if they are in "chars". If "chars" is not provided, it defaults to " " (a space). If the directional argument is not provided, it defaults to "BOTH".</td></tr> |
| <tr><td><code>BTRIM(expr[, chars])</code></td><td>Alternate form of <code>TRIM(BOTH <chars> FROM <expr></code>).</td></tr> |
| <tr><td><code>LTRIM(expr[, chars])</code></td><td>Alternate form of <code>TRIM(LEADING <chars> FROM <expr></code>).</td></tr> |
| <tr><td><code>RTRIM(expr[, chars])</code></td><td>Alternate form of <code>TRIM(TRAILING <chars> FROM <expr></code>).</td></tr> |
| <tr><td><code>UPPER(expr)</code></td><td>Returns expr in all uppercase.</td></tr> |
| <tr><td><code>REVERSE(expr)</code></td><td>Reverses expr.</td></tr> |
| <tr><td><code>REPEAT(expr, [N])</code></td><td>Repeats expr N times</td></tr> |
| <tr><td><code>LPAD(expr, length[, chars])</code></td><td>Returns a string of "length" from "expr" left-padded with "chars". If "length" is shorter than the length of "expr", the result is "expr" which is truncated to "length". If either "expr" or "chars" are null, the result will be null.</td></tr> |
| <tr><td><code>RPAD(expr, length[, chars])</code></td><td>Returns a string of "length" from "expr" right-padded with "chars". If "length" is shorter than the length of "expr", the result is "expr" which is truncated to "length". If either "expr" or "chars" are null, the result will be null.</td></tr> |
| </tbody> |
| </table> |
| <h3><a class="anchor" aria-hidden="true" id="time-functions"></a><a href="#time-functions" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Time functions</h3> |
| <p>Time functions can be used with Druid's <code>__time</code> column, with any column storing millisecond timestamps through use |
| of the <code>MILLIS_TO_TIMESTAMP</code> function, or with any column storing string timestamps through use of the <code>TIME_PARSE</code> |
| function. By default, time operations use the UTC time zone. You can change the time zone by setting the connection |
| context parameter "sqlTimeZone" to the name of another time zone, like "America/Los_Angeles", or to an offset like |
| "-08:00". If you need to mix multiple time zones in the same query, or if you need to use a time zone other than |
| the connection time zone, some functions also accept time zones as parameters. These parameters always take precedence |
| over the connection time zone.</p> |
| <p>Literal timestamps in the connection time zone can be written using <code>TIMESTAMP '2000-01-01 00:00:00'</code> syntax. The |
| simplest way to write literal timestamps in other time zones is to use TIME_PARSE, like |
| <code>TIME_PARSE('2000-02-01 00:00:00', NULL, 'America/Los_Angeles')</code>.</p> |
| <table> |
| <thead> |
| <tr><th>Function</th><th>Notes</th></tr> |
| </thead> |
| <tbody> |
| <tr><td><code>CURRENT_TIMESTAMP</code></td><td>Current timestamp in the connection's time zone.</td></tr> |
| <tr><td><code>CURRENT_DATE</code></td><td>Current date in the connection's time zone.</td></tr> |
| <tr><td><code>DATE_TRUNC(<unit>, <timestamp_expr>)</code></td><td>Rounds down a timestamp, returning it as a new timestamp. Unit can be 'milliseconds', 'second', 'minute', 'hour', 'day', 'week', 'month', 'quarter', 'year', 'decade', 'century', or 'millennium'.</td></tr> |
| <tr><td><code>TIME_CEIL(<timestamp_expr>, <period>, [<origin>, [<timezone>]])</code></td><td>Rounds up a timestamp, returning it as a new timestamp. Period can be any ISO8601 period, like P3M (quarters) or PT12H (half-days). The time zone, if provided, should be a time zone name like "America/Los_Angeles" or offset like "-08:00". This function is similar to <code>CEIL</code> but is more flexible.</td></tr> |
| <tr><td><code>TIME_FLOOR(<timestamp_expr>, <period>, [<origin>, [<timezone>]])</code></td><td>Rounds down a timestamp, returning it as a new timestamp. Period can be any ISO8601 period, like P3M (quarters) or PT12H (half-days). The time zone, if provided, should be a time zone name like "America/Los_Angeles" or offset like "-08:00". This function is similar to <code>FLOOR</code> but is more flexible.</td></tr> |
| <tr><td><code>TIME_SHIFT(<timestamp_expr>, <period>, <step>, [<timezone>])</code></td><td>Shifts a timestamp by a period (step times), returning it as a new timestamp. Period can be any ISO8601 period. Step may be negative. The time zone, if provided, should be a time zone name like "America/Los_Angeles" or offset like "-08:00".</td></tr> |
| <tr><td><code>TIME_EXTRACT(<timestamp_expr>, [<unit>, [<timezone>]])</code></td><td>Extracts a time part from expr, returning it as a number. Unit can be EPOCH, SECOND, MINUTE, HOUR, DAY (day of month), DOW (day of week), DOY (day of year), WEEK (week of <a href="https://en.wikipedia.org/wiki/ISO_week_date">week year</a>), MONTH (1 through 12), QUARTER (1 through 4), or YEAR. The time zone, if provided, should be a time zone name like "America/Los_Angeles" or offset like "-08:00". This function is similar to <code>EXTRACT</code> but is more flexible. Unit and time zone must be literals, and must be provided quoted, like <code>TIME_EXTRACT(__time, 'HOUR')</code> or <code>TIME_EXTRACT(__time, 'HOUR', 'America/Los_Angeles')</code>.</td></tr> |
| <tr><td><code>TIME_PARSE(<string_expr>, [<pattern>, [<timezone>]])</code></td><td>Parses a string into a timestamp using a given <a href="http://www.joda.org/joda-time/apidocs/org/joda/time/format/DateTimeFormat.html">Joda DateTimeFormat pattern</a>, or ISO8601 (e.g. <code>2000-01-02T03:04:05Z</code>) if the pattern is not provided. The time zone, if provided, should be a time zone name like "America/Los_Angeles" or offset like "-08:00", and will be used as the time zone for strings that do not include a time zone offset. Pattern and time zone must be literals. Strings that cannot be parsed as timestamps will be returned as NULL.</td></tr> |
| <tr><td><code>TIME_FORMAT(<timestamp_expr>, [<pattern>, [<timezone>]])</code></td><td>Formats a timestamp as a string with a given <a href="http://www.joda.org/joda-time/apidocs/org/joda/time/format/DateTimeFormat.html">Joda DateTimeFormat pattern</a>, or ISO8601 (e.g. <code>2000-01-02T03:04:05Z</code>) if the pattern is not provided. The time zone, if provided, should be a time zone name like "America/Los_Angeles" or offset like "-08:00". Pattern and time zone must be literals.</td></tr> |
| <tr><td><code>MILLIS_TO_TIMESTAMP(millis_expr)</code></td><td>Converts a number of milliseconds since the epoch into a timestamp.</td></tr> |
| <tr><td><code>TIMESTAMP_TO_MILLIS(timestamp_expr)</code></td><td>Converts a timestamp into a number of milliseconds since the epoch.</td></tr> |
| <tr><td><code>EXTRACT(<unit> FROM timestamp_expr)</code></td><td>Extracts a time part from expr, returning it as a number. Unit can be EPOCH, MICROSECOND, MILLISECOND, SECOND, MINUTE, HOUR, DAY (day of month), DOW (day of week), ISODOW (ISO day of week), DOY (day of year), WEEK (week of year), MONTH, QUARTER, YEAR, ISOYEAR, DECADE, CENTURY or MILLENNIUM. Units must be provided unquoted, like <code>EXTRACT(HOUR FROM __time)</code>.</td></tr> |
| <tr><td><code>FLOOR(timestamp_expr TO <unit>)</code></td><td>Rounds down a timestamp, returning it as a new timestamp. Unit can be SECOND, MINUTE, HOUR, DAY, WEEK, MONTH, QUARTER, or YEAR.</td></tr> |
| <tr><td><code>CEIL(timestamp_expr TO <unit>)</code></td><td>Rounds up a timestamp, returning it as a new timestamp. Unit can be SECOND, MINUTE, HOUR, DAY, WEEK, MONTH, QUARTER, or YEAR.</td></tr> |
| <tr><td><code>TIMESTAMPADD(<unit>, <count>, <timestamp>)</code></td><td>Equivalent to <code>timestamp + count * INTERVAL '1' UNIT</code>.</td></tr> |
| <tr><td><code>TIMESTAMPDIFF(<unit>, <timestamp1>, <timestamp2>)</code></td><td>Returns the (signed) number of <code>unit</code> between <code>timestamp1</code> and <code>timestamp2</code>. Unit can be SECOND, MINUTE, HOUR, DAY, WEEK, MONTH, QUARTER, or YEAR.</td></tr> |
| <tr><td><code>timestamp_expr { + | - } <interval_expr><code></td><td>Add or subtract an amount of time from a timestamp. interval_expr can include interval literals like <code>INTERVAL '2' HOUR</code>, and may include interval arithmetic as well. This operator treats days as uniformly 86400 seconds long, and does not take into account daylight savings time. To account for daylight savings time, use TIME_SHIFT instead.</td></tr> |
| </tbody> |
| </table> |
| <h3><a class="anchor" aria-hidden="true" id="ip-address-functions"></a><a href="#ip-address-functions" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>IP address functions</h3> |
| <p>For the IPv4 address functions, the <code>address</code> argument can either be an IPv4 dotted-decimal string |
| (e.g., '192.168.0.1') or an IP address represented as an integer (e.g., 3232235521). The <code>subnet</code> |
| argument should be a string formatted as an IPv4 address subnet in CIDR notation (e.g., |
| '192.168.0.0/16').</p> |
| <table> |
| <thead> |
| <tr><th>Function</th><th>Notes</th></tr> |
| </thead> |
| <tbody> |
| <tr><td><code>IPV4_MATCH(address, subnet)</code></td><td>Returns true if the <code>address</code> belongs to the <code>subnet</code> literal, else false. If <code>address</code> is not a valid IPv4 address, then false is returned. This function is more efficient if <code>address</code> is an integer instead of a string.</td></tr> |
| <tr><td><code>IPV4_PARSE(address)</code></td><td>Parses <code>address</code> into an IPv4 address stored as an integer . If <code>address</code> is an integer that is a valid IPv4 address, then it is passed through. Returns null if <code>address</code> cannot be represented as an IPv4 address.</td></tr> |
| <tr><td><code>IPV4_STRINGIFY(address)</code></td><td>Converts <code>address</code> into an IPv4 address dotted-decimal string. If <code>address</code> is a string that is a valid IPv4 address, then it is passed through. Returns null if <code>address</code> cannot be represented as an IPv4 address.</td></tr> |
| </tbody> |
| </table> |
| <h3><a class="anchor" aria-hidden="true" id="comparison-operators"></a><a href="#comparison-operators" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Comparison operators</h3> |
| <table> |
| <thead> |
| <tr><th>Function</th><th>Notes</th></tr> |
| </thead> |
| <tbody> |
| <tr><td><code>x = y</code></td><td>Equals.</td></tr> |
| <tr><td><code>x <> y</code></td><td>Not-equals.</td></tr> |
| <tr><td><code>x > y</code></td><td>Greater than.</td></tr> |
| <tr><td><code>x >= y</code></td><td>Greater than or equal to.</td></tr> |
| <tr><td><code>x < y</code></td><td>Less than.</td></tr> |
| <tr><td><code>x <= y</code></td><td>Less than or equal to.</td></tr> |
| <tr><td><code>x BETWEEN y AND z</code></td><td>Equivalent to <code>x >= y AND x <= z</code>.</td></tr> |
| <tr><td><code>x NOT BETWEEN y AND z</code></td><td>Equivalent to <code>x < y OR x > z</code>.</td></tr> |
| <tr><td><code>x LIKE pattern [ESCAPE esc]</code></td><td>True if x matches a SQL LIKE pattern (with an optional escape).</td></tr> |
| <tr><td><code>x NOT LIKE pattern [ESCAPE esc]</code></td><td>True if x does not match a SQL LIKE pattern (with an optional escape).</td></tr> |
| <tr><td><code>x IS NULL</code></td><td>True if x is NULL or empty string.</td></tr> |
| <tr><td><code>x IS NOT NULL</code></td><td>True if x is neither NULL nor empty string.</td></tr> |
| <tr><td><code>x IS TRUE</code></td><td>True if x is true.</td></tr> |
| <tr><td><code>x IS NOT TRUE</code></td><td>True if x is not true.</td></tr> |
| <tr><td><code>x IS FALSE</code></td><td>True if x is false.</td></tr> |
| <tr><td><code>x IS NOT FALSE</code></td><td>True if x is not false.</td></tr> |
| <tr><td><code>x IN (values)</code></td><td>True if x is one of the listed values.</td></tr> |
| <tr><td><code>x NOT IN (values)</code></td><td>True if x is not one of the listed values.</td></tr> |
| <tr><td><code>x IN (subquery)</code></td><td>True if x is returned by the subquery. See <a href="#query-execution">Query execution</a> above for details about how Druid SQL handles <code>IN (subquery)</code>.</td></tr> |
| <tr><td><code>x NOT IN (subquery)</code></td><td>True if x is not returned by the subquery. See <a href="#query-execution">Query execution</a> for details about how Druid SQL handles <code>IN (subquery)</code>.</td></tr> |
| <tr><td><code>x AND y</code></td><td>Boolean AND.</td></tr> |
| <tr><td><code>x OR y</code></td><td>Boolean OR.</td></tr> |
| <tr><td><code>NOT x</code></td><td>Boolean NOT.</td></tr> |
| </tbody> |
| </table> |
| <h3><a class="anchor" aria-hidden="true" id="multi-value-string-functions"></a><a href="#multi-value-string-functions" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Multi-value string functions</h3> |
| <p>All 'array' references in the multi-value string function documentation can refer to multi-value string columns or |
| <code>ARRAY</code> literals.</p> |
| <table> |
| <thead> |
| <tr><th>Function</th><th>Notes</th></tr> |
| </thead> |
| <tbody> |
| <tr><td><code>ARRAY(expr1,expr ...)</code></td><td>constructs an SQL ARRAY literal from the expression arguments, using the type of the first argument as the output array type</td></tr> |
| <tr><td><code>MV_LENGTH(arr)</code></td><td>returns length of array expression</td></tr> |
| <tr><td><code>MV_OFFSET(arr,long)</code></td><td>returns the array element at the 0 based index supplied, or null for an out of range index</td></tr> |
| <tr><td><code>MV_ORDINAL(arr,long)</code></td><td>returns the array element at the 1 based index supplied, or null for an out of range index</td></tr> |
| <tr><td><code>MV_CONTAINS(arr,expr)</code></td><td>returns 1 if the array contains the element specified by expr, or contains all elements specified by expr if expr is an array, else 0</td></tr> |
| <tr><td><code>MV_OVERLAP(arr1,arr2)</code></td><td>returns 1 if arr1 and arr2 have any elements in common, else 0</td></tr> |
| <tr><td><code>MV_OFFSET_OF(arr,expr)</code></td><td>returns the 0 based index of the first occurrence of expr in the array, or <code>-1</code> or <code>null</code> if <code>druid.generic.useDefaultValueForNull=false</code> if no matching elements exist in the array.</td></tr> |
| <tr><td><code>MV_ORDINAL_OF(arr,expr)</code></td><td>returns the 1 based index of the first occurrence of expr in the array, or <code>-1</code> or <code>null</code> if <code>druid.generic.useDefaultValueForNull=false</code> if no matching elements exist in the array.</td></tr> |
| <tr><td><code>MV_PREPEND(expr,arr)</code></td><td>adds expr to arr at the beginning, the resulting array type determined by the type of the array</td></tr> |
| <tr><td><code>MV_APPEND(arr1,expr)</code></td><td>appends expr to arr, the resulting array type determined by the type of the first array</td></tr> |
| <tr><td><code>MV_CONCAT(arr1,arr2)</code></td><td>concatenates 2 arrays, the resulting array type determined by the type of the first array</td></tr> |
| <tr><td><code>MV_SLICE(arr,start,end)</code></td><td>return the subarray of arr from the 0 based index start(inclusive) to end(exclusive), or <code>null</code>, if start is less than 0, greater than length of arr or less than end</td></tr> |
| <tr><td><code>MV_TO_STRING(arr,str)</code></td><td>joins all elements of arr by the delimiter specified by str</td></tr> |
| <tr><td><code>STRING_TO_MV(str1,str2)</code></td><td>splits str1 into an array on the delimiter specified by str2</td></tr> |
| </tbody> |
| </table> |
| <h3><a class="anchor" aria-hidden="true" id="other-functions"></a><a href="#other-functions" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Other functions</h3> |
| <table> |
| <thead> |
| <tr><th>Function</th><th>Notes</th></tr> |
| </thead> |
| <tbody> |
| <tr><td><code>CAST(value AS TYPE)</code></td><td>Cast value to another type. See <a href="#data-types-and-casts">Data types and casts</a> for details about how Druid SQL handles CAST.</td></tr> |
| <tr><td><code>CASE expr WHEN value1 THEN result1 \[ WHEN value2 THEN result2 ... \] \[ ELSE resultN \] END</code></td><td>Simple CASE.</td></tr> |
| <tr><td><code>CASE WHEN boolean_expr1 THEN result1 \[ WHEN boolean_expr2 THEN result2 ... \] \[ ELSE resultN \] END</code></td><td>Searched CASE.</td></tr> |
| <tr><td><code>NULLIF(value1, value2)</code></td><td>Returns NULL if value1 and value2 match, else returns value1.</td></tr> |
| <tr><td><code>COALESCE(value1, value2, ...)</code></td><td>Returns the first value that is neither NULL nor empty string.</td></tr> |
| <tr><td><code>NVL(expr,expr-for-null)</code></td><td>Returns 'expr-for-null' if 'expr' is null (or empty string for string type).</td></tr> |
| <tr><td><code>BLOOM_FILTER_TEST(<expr>, <serialized-filter>)</code></td><td>Returns true if the value is contained in the base64 serialized bloom filter. See <a href="../development/extensions-core/bloom-filter.html">bloom filter extension</a> documentation for additional details.</td></tr> |
| </tbody> |
| </table> |
| <h3><a class="anchor" aria-hidden="true" id="unsupported-features"></a><a href="#unsupported-features" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Unsupported features</h3> |
| <p>Druid does not support all SQL features, including:</p> |
| <ul> |
| <li>OVER clauses, and analytic functions such as <code>LAG</code> and <code>LEAD</code>.</li> |
| <li>JOIN clauses, other than semi-joins as described above.</li> |
| <li>OFFSET clauses.</li> |
| <li>DDL and DML.</li> |
| </ul> |
| <p>Additionally, some Druid features are not supported by the SQL language. Some unsupported Druid features include:</p> |
| <ul> |
| <li><a href="multi-value-dimensions.html">Multi-value dimensions</a>.</li> |
| <li><a href="../development/extensions-core/datasketches-extension.html">Set operations on DataSketches aggregators</a>.</li> |
| <li><a href="../development/geo.html">Spatial filters</a>.</li> |
| <li><a href="querying.html#query-cancellation">Query cancellation</a>.</li> |
| </ul> |
| <h2><a class="anchor" aria-hidden="true" id="query-execution"></a><a href="#query-execution" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Query execution</h2> |
| <p>Queries without aggregations will use Druid's <a href="scan-query.html">Scan</a> native query type.</p> |
| <p>Aggregation queries (using GROUP BY, DISTINCT, or any aggregation functions) will use one of Druid's three native |
| aggregation query types. Two (Timeseries and TopN) are specialized for specific types of aggregations, whereas the other |
| (GroupBy) is general-purpose.</p> |
| <ul> |
| <li><p><a href="timeseriesquery.html">Timeseries</a> is used for queries that GROUP BY <code>FLOOR(__time TO <unit>)</code> or <code>TIME_FLOOR(__time, period)</code>, have no other grouping expressions, no HAVING or LIMIT clauses, no nesting, and either no ORDER BY, or an |
| ORDER BY that orders by same expression as present in GROUP BY. It also uses Timeseries for "grand total" queries that |
| have aggregation functions but no GROUP BY. This query type takes advantage of the fact that Druid segments are sorted |
| by time.</p></li> |
| <li><p><a href="topnquery.html">TopN</a> is used by default for queries that group by a single expression, do have ORDER BY and LIMIT |
| clauses, do not have HAVING clauses, and are not nested. However, the TopN query type will deliver approximate ranking |
| and results in some cases; if you want to avoid this, set "useApproximateTopN" to "false". TopN results are always |
| computed in memory. See the TopN documentation for more details.</p></li> |
| <li><p><a href="groupbyquery.html">GroupBy</a> is used for all other aggregations, including any nested aggregation queries. Druid's |
| GroupBy is a traditional aggregation engine: it delivers exact results and rankings and supports a wide variety of |
| features. GroupBy aggregates in memory if it can, but it may spill to disk if it doesn't have enough memory to complete |
| your query. Results are streamed back from data processes through the Broker if you ORDER BY the same expressions in your |
| GROUP BY clause, or if you don't have an ORDER BY at all. If your query has an ORDER BY referencing expressions that |
| don't appear in the GROUP BY clause (like aggregation functions) then the Broker will materialize a list of results in |
| memory, up to a max of your LIMIT, if any. See the GroupBy documentation for details about tuning performance and memory |
| use.</p></li> |
| </ul> |
| <p>If your query does nested aggregations (an aggregation subquery in your FROM clause) then Druid will execute it as a |
| <a href="groupbyquery.html#nested-groupbys">nested GroupBy</a>. In nested GroupBys, the innermost aggregation is distributed, but |
| all outer aggregations beyond that take place locally on the query Broker.</p> |
| <p>Semi-join queries containing WHERE clauses like <code>col IN (SELECT expr FROM ...)</code> are executed with a special process. The |
| Broker will first translate the subquery into a GroupBy to find distinct values of <code>expr</code>. Then, the broker will rewrite |
| the subquery to a literal filter, like <code>col IN (val1, val2, ...)</code> and run the outer query. The configuration parameter |
| druid.sql.planner.maxSemiJoinRowsInMemory controls the maximum number of values that will be materialized for this kind |
| of plan.</p> |
| <p>For all native query types, filters on the <code>__time</code> column will be translated into top-level query "intervals" whenever |
| possible, which allows Druid to use its global time index to quickly prune the set of data that must be scanned. In |
| addition, Druid will use indexes local to each data process to further speed up WHERE evaluation. This can typically be |
| done for filters that involve boolean combinations of references to and functions of single columns, like |
| <code>WHERE col1 = 'a' AND col2 = 'b'</code>, but not <code>WHERE col1 = col2</code>.</p> |
| <h3><a class="anchor" aria-hidden="true" id="approximate-algorithms"></a><a href="#approximate-algorithms" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Approximate algorithms</h3> |
| <p>Druid SQL will use approximate algorithms in some situations:</p> |
| <ul> |
| <li>The <code>COUNT(DISTINCT col)</code> aggregation functions by default uses a variant of |
| <a href="http://algo.inria.fr/flajolet/Publications/FlFuGaMe07.pdf">HyperLogLog</a>, a fast approximate distinct counting |
| algorithm. Druid SQL will switch to exact distinct counts if you set "useApproximateCountDistinct" to "false", either |
| through query context or through Broker configuration.</li> |
| <li>GROUP BY queries over a single column with ORDER BY and LIMIT may be executed using the TopN engine, which uses an |
| approximate algorithm. Druid SQL will switch to an exact grouping algorithm if you set "useApproximateTopN" to "false", |
| either through query context or through Broker configuration.</li> |
| <li>The APPROX_COUNT_DISTINCT and APPROX_QUANTILE aggregation functions always use approximate algorithms, regardless |
| of configuration.</li> |
| </ul> |
| <h2><a class="anchor" aria-hidden="true" id="client-apis"></a><a href="#client-apis" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Client APIs</h2> |
| <h3><a class="anchor" aria-hidden="true" id="json-over-http"></a><a href="#json-over-http" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>JSON over HTTP</h3> |
| <p>You can make Druid SQL queries using JSON over HTTP by posting to the endpoint <code>/druid/v2/sql/</code>. The request should |
| be a JSON object with a "query" field, like <code>{"query" : "SELECT COUNT(*) FROM data_source WHERE foo = 'bar'"}</code>.</p> |
| <p>You can use <em>curl</em> to send SQL queries from the command-line:</p> |
| <pre><code class="hljs css language-bash">$ cat query.json |
| {<span class="hljs-string">"query"</span>:<span class="hljs-string">"SELECT COUNT(*) AS TheCount FROM data_source"</span>} |
| |
| $ curl -XPOST -H<span class="hljs-string">'Content-Type: application/json'</span> http://BROKER:8082/druid/v2/sql/ -d @query.json |
| [{<span class="hljs-string">"TheCount"</span>:24433}] |
| </code></pre> |
| <p>There are a variety of <a href="#connection-context">connection context parameters</a> you can provide by adding a "context" map, |
| like:</p> |
| <pre><code class="hljs css language-json">{ |
| <span class="hljs-attr">"query"</span> : <span class="hljs-string">"SELECT COUNT(*) FROM data_source WHERE foo = 'bar' AND __time > TIMESTAMP '2000-01-01 00:00:00'"</span>, |
| <span class="hljs-attr">"context"</span> : { |
| <span class="hljs-attr">"sqlTimeZone"</span> : <span class="hljs-string">"America/Los_Angeles"</span> |
| } |
| } |
| </code></pre> |
| <p>Metadata is available over the HTTP API by querying <a href="#metadata-tables">system tables</a>.</p> |
| <h4><a class="anchor" aria-hidden="true" id="responses"></a><a href="#responses" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Responses</h4> |
| <p>Druid SQL supports a variety of result formats. You can specify these by adding a "resultFormat" parameter, like:</p> |
| <pre><code class="hljs css language-json">{ |
| <span class="hljs-attr">"query"</span> : <span class="hljs-string">"SELECT COUNT(*) FROM data_source WHERE foo = 'bar' AND __time > TIMESTAMP '2000-01-01 00:00:00'"</span>, |
| <span class="hljs-attr">"resultFormat"</span> : <span class="hljs-string">"object"</span> |
| } |
| </code></pre> |
| <p>The supported result formats are:</p> |
| <table> |
| <thead> |
| <tr><th>Format</th><th>Description</th><th>Content-Type</th></tr> |
| </thead> |
| <tbody> |
| <tr><td><code>object</code></td><td>The default, a JSON array of JSON objects. Each object's field names match the columns returned by the SQL query, and are provided in the same order as the SQL query.</td><td>application/json</td></tr> |
| <tr><td><code>array</code></td><td>JSON array of JSON arrays. Each inner array has elements matching the columns returned by the SQL query, in order.</td><td>application/json</td></tr> |
| <tr><td><code>objectLines</code></td><td>Like "object", but the JSON objects are separated by newlines instead of being wrapped in a JSON array. This can make it easier to parse the entire response set as a stream, if you do not have ready access to a streaming JSON parser. To make it possible to detect a truncated response, this format includes a trailer of one blank line.</td><td>text/plain</td></tr> |
| <tr><td><code>arrayLines</code></td><td>Like "array", but the JSON arrays are separated by newlines instead of being wrapped in a JSON array. This can make it easier to parse the entire response set as a stream, if you do not have ready access to a streaming JSON parser. To make it possible to detect a truncated response, this format includes a trailer of one blank line.</td><td>text/plain</td></tr> |
| <tr><td><code>csv</code></td><td>Comma-separated values, with one row per line. Individual field values may be escaped by being surrounded in double quotes. If double quotes appear in a field value, they will be escaped by replacing them with double-double-quotes like <code>""this""</code>. To make it possible to detect a truncated response, this format includes a trailer of one blank line.</td><td>text/csv</td></tr> |
| </tbody> |
| </table> |
| <p>You can additionally request a header by setting "header" to true in your request, like:</p> |
| <pre><code class="hljs css language-json">{ |
| <span class="hljs-attr">"query"</span> : <span class="hljs-string">"SELECT COUNT(*) FROM data_source WHERE foo = 'bar' AND __time > TIMESTAMP '2000-01-01 00:00:00'"</span>, |
| <span class="hljs-attr">"resultFormat"</span> : <span class="hljs-string">"arrayLines"</span>, |
| <span class="hljs-attr">"header"</span> : <span class="hljs-literal">true</span> |
| } |
| </code></pre> |
| <p>In this case, the first result returned will be a header. For the <code>csv</code>, <code>array</code>, and <code>arrayLines</code> formats, the header |
| will be a list of column names. For the <code>object</code> and <code>objectLines</code> formats, the header will be an object where the |
| keys are column names, and the values are null.</p> |
| <p>Errors that occur before the response body is sent will be reported in JSON, with an HTTP 500 status code, in the |
| same format as <a href="../querying/querying.html#query-errors">native Druid query errors</a>. If an error occurs while the response body is |
| being sent, at that point it is too late to change the HTTP status code or report a JSON error, so the response will |
| simply end midstream and an error will be logged by the Druid server that was handling your request.</p> |
| <p>As a caller, it is important that you properly handle response truncation. This is easy for the "object" and "array" |
| formats, since truncated responses will be invalid JSON. For the line-oriented formats, you should check the |
| trailer they all include: one blank line at the end of the result set. If you detect a truncated response, either |
| through a JSON parsing error or through a missing trailing newline, you should assume the response was not fully |
| delivered due to an error.</p> |
| <h3><a class="anchor" aria-hidden="true" id="jdbc"></a><a href="#jdbc" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>JDBC</h3> |
| <p>You can make Druid SQL queries using the <a href="https://calcite.apache.org/avatica/downloads/">Avatica JDBC driver</a>. Once |
| you've downloaded the Avatica client jar, add it to your classpath and use the connect string |
| <code>jdbc:avatica:remote:url=http://BROKER:8082/druid/v2/sql/avatica/</code>.</p> |
| <p>Example code:</p> |
| <pre><code class="hljs css language-java"><span class="hljs-comment">// Connect to /druid/v2/sql/avatica/ on your Broker.</span> |
| String url = <span class="hljs-string">"jdbc:avatica:remote:url=http://localhost:8082/druid/v2/sql/avatica/"</span>; |
| |
| <span class="hljs-comment">// Set any connection context parameters you need here (see "Connection context" below).</span> |
| <span class="hljs-comment">// Or leave empty for default behavior.</span> |
| Properties connectionProperties = <span class="hljs-keyword">new</span> Properties(); |
| |
| <span class="hljs-keyword">try</span> (Connection connection = DriverManager.getConnection(url, connectionProperties)) { |
| <span class="hljs-keyword">try</span> ( |
| <span class="hljs-keyword">final</span> Statement statement = connection.createStatement(); |
| <span class="hljs-keyword">final</span> ResultSet resultSet = statement.executeQuery(query) |
| ) { |
| <span class="hljs-keyword">while</span> (resultSet.next()) { |
| <span class="hljs-comment">// Do something</span> |
| } |
| } |
| } |
| </code></pre> |
| <p>Table metadata is available over JDBC using <code>connection.getMetaData()</code> or by querying the |
| <a href="#metadata-tables">"INFORMATION_SCHEMA" tables</a>. Parameterized queries (using <code>?</code> or other placeholders) don't work properly, |
| so avoid those.</p> |
| <h4><a class="anchor" aria-hidden="true" id="connection-stickiness"></a><a href="#connection-stickiness" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Connection stickiness</h4> |
| <p>Druid's JDBC server does not share connection state between Brokers. This means that if you're using JDBC and have |
| multiple Druid Brokers, you should either connect to a specific Broker, or use a load balancer with sticky sessions |
| enabled. The Druid Router process provides connection stickiness when balancing JDBC requests, and can be used to achieve |
| the necessary stickiness even with a normal non-sticky load balancer. Please see the |
| <a href="/docs/0.16.1-incubating/design/router.html">Router</a> documentation for more details.</p> |
| <p>Note that the non-JDBC <a href="#json-over-http">JSON over HTTP</a> API is stateless and does not require stickiness.</p> |
| <h3><a class="anchor" aria-hidden="true" id="connection-context"></a><a href="#connection-context" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Connection context</h3> |
| <p>Druid SQL supports setting connection parameters on the client. The parameters in the table below affect SQL planning. |
| All other context parameters you provide will be attached to Druid queries and can affect how they run. See |
| <a href="query-context.html">Query context</a> for details on the possible options.</p> |
| <p>Note that to specify an unique identifier for SQL query, use <code>sqlQueryId</code> instead of <code>queryId</code>. Setting <code>queryId</code> for a SQL |
| request has no effect, all native queries underlying SQL will use auto-generated queryId.</p> |
| <p>Connection context can be specified as JDBC connection properties or as a "context" object in the JSON API.</p> |
| <table> |
| <thead> |
| <tr><th>Parameter</th><th>Description</th><th>Default value</th></tr> |
| </thead> |
| <tbody> |
| <tr><td><code>sqlQueryId</code></td><td>Unique identifier given to this SQL query. For HTTP client, it will be returned in <code>X-Druid-SQL-Query-Id</code> header.</td><td>auto-generated</td></tr> |
| <tr><td><code>sqlTimeZone</code></td><td>Sets the time zone for this connection, which will affect how time functions and timestamp literals behave. Should be a time zone name like "America/Los_Angeles" or offset like "-08:00".</td><td>druid.sql.planner.sqlTimeZone on the Broker (default: UTC)</td></tr> |
| <tr><td><code>useApproximateCountDistinct</code></td><td>Whether to use an approximate cardinality algorithm for <code>COUNT(DISTINCT foo)</code>.</td><td>druid.sql.planner.useApproximateCountDistinct on the Broker (default: true)</td></tr> |
| <tr><td><code>useApproximateTopN</code></td><td>Whether to use approximate <a href="topnquery.html">TopN queries</a> when a SQL query could be expressed as such. If false, exact <a href="groupbyquery.html">GroupBy queries</a> will be used instead.</td><td>druid.sql.planner.useApproximateTopN on the Broker (default: true)</td></tr> |
| </tbody> |
| </table> |
| <h2><a class="anchor" aria-hidden="true" id="metadata-tables"></a><a href="#metadata-tables" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Metadata tables</h2> |
| <p>Druid Brokers infer table and column metadata for each datasource from segments loaded in the cluster, and use this to |
| plan SQL queries. This metadata is cached on Broker startup and also updated periodically in the background through |
| <a href="segmentmetadataquery.html">SegmentMetadata queries</a>. Background metadata refreshing is triggered by |
| segments entering and exiting the cluster, and can also be throttled through configuration.</p> |
| <p>Druid exposes system information through special system tables. There are two such schemas available: Information Schema and Sys Schema. |
| Information schema provides details about table and column types. The "sys" schema provides information about Druid internals like segments/tasks/servers.</p> |
| <h3><a class="anchor" aria-hidden="true" id="information-schema"></a><a href="#information-schema" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>INFORMATION SCHEMA</h3> |
| <p>You can access table and column metadata through JDBC using <code>connection.getMetaData()</code>, or through the |
| INFORMATION_SCHEMA tables described below. For example, to retrieve metadata for the Druid |
| datasource "foo", use the query:</p> |
| <pre><code class="hljs css language-sql"><span class="hljs-keyword">SELECT</span> * <span class="hljs-keyword">FROM</span> INFORMATION_SCHEMA.COLUMNS <span class="hljs-keyword">WHERE</span> TABLE_SCHEMA = <span class="hljs-string">'druid'</span> <span class="hljs-keyword">AND</span> TABLE_NAME = <span class="hljs-string">'foo'</span> |
| </code></pre> |
| <h4><a class="anchor" aria-hidden="true" id="schemata-table"></a><a href="#schemata-table" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>SCHEMATA table</h4> |
| <table> |
| <thead> |
| <tr><th>Column</th><th>Notes</th></tr> |
| </thead> |
| <tbody> |
| <tr><td>CATALOG_NAME</td><td>Unused</td></tr> |
| <tr><td>SCHEMA_NAME</td><td></td></tr> |
| <tr><td>SCHEMA_OWNER</td><td>Unused</td></tr> |
| <tr><td>DEFAULT_CHARACTER_SET_CATALOG</td><td>Unused</td></tr> |
| <tr><td>DEFAULT_CHARACTER_SET_SCHEMA</td><td>Unused</td></tr> |
| <tr><td>DEFAULT_CHARACTER_SET_NAME</td><td>Unused</td></tr> |
| <tr><td>SQL_PATH</td><td>Unused</td></tr> |
| </tbody> |
| </table> |
| <h4><a class="anchor" aria-hidden="true" id="tables-table"></a><a href="#tables-table" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>TABLES table</h4> |
| <table> |
| <thead> |
| <tr><th>Column</th><th>Notes</th></tr> |
| </thead> |
| <tbody> |
| <tr><td>TABLE_CATALOG</td><td>Unused</td></tr> |
| <tr><td>TABLE_SCHEMA</td><td></td></tr> |
| <tr><td>TABLE_NAME</td><td></td></tr> |
| <tr><td>TABLE_TYPE</td><td>"TABLE" or "SYSTEM_TABLE"</td></tr> |
| </tbody> |
| </table> |
| <h4><a class="anchor" aria-hidden="true" id="columns-table"></a><a href="#columns-table" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>COLUMNS table</h4> |
| <table> |
| <thead> |
| <tr><th>Column</th><th>Notes</th></tr> |
| </thead> |
| <tbody> |
| <tr><td>TABLE_CATALOG</td><td>Unused</td></tr> |
| <tr><td>TABLE_SCHEMA</td><td></td></tr> |
| <tr><td>TABLE_NAME</td><td></td></tr> |
| <tr><td>COLUMN_NAME</td><td></td></tr> |
| <tr><td>ORDINAL_POSITION</td><td></td></tr> |
| <tr><td>COLUMN_DEFAULT</td><td>Unused</td></tr> |
| <tr><td>IS_NULLABLE</td><td></td></tr> |
| <tr><td>DATA_TYPE</td><td></td></tr> |
| <tr><td>CHARACTER_MAXIMUM_LENGTH</td><td>Unused</td></tr> |
| <tr><td>CHARACTER_OCTET_LENGTH</td><td>Unused</td></tr> |
| <tr><td>NUMERIC_PRECISION</td><td></td></tr> |
| <tr><td>NUMERIC_PRECISION_RADIX</td><td></td></tr> |
| <tr><td>NUMERIC_SCALE</td><td></td></tr> |
| <tr><td>DATETIME_PRECISION</td><td></td></tr> |
| <tr><td>CHARACTER_SET_NAME</td><td></td></tr> |
| <tr><td>COLLATION_NAME</td><td></td></tr> |
| <tr><td>JDBC_TYPE</td><td>Type code from java.sql.Types (Druid extension)</td></tr> |
| </tbody> |
| </table> |
| <h3><a class="anchor" aria-hidden="true" id="system-schema"></a><a href="#system-schema" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>SYSTEM SCHEMA</h3> |
| <p>The "sys" schema provides visibility into Druid segments, servers and tasks.</p> |
| <h4><a class="anchor" aria-hidden="true" id="segments-table"></a><a href="#segments-table" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>SEGMENTS table</h4> |
| <p>Segments table provides details on all Druid segments, whether they are published yet or not.</p> |
| <table> |
| <thead> |
| <tr><th>Column</th><th>Type</th><th>Notes</th></tr> |
| </thead> |
| <tbody> |
| <tr><td>segment_id</td><td>STRING</td><td>Unique segment identifier</td></tr> |
| <tr><td>datasource</td><td>STRING</td><td>Name of datasource</td></tr> |
| <tr><td>start</td><td>STRING</td><td>Interval start time (in ISO 8601 format)</td></tr> |
| <tr><td>end</td><td>STRING</td><td>Interval end time (in ISO 8601 format)</td></tr> |
| <tr><td>size</td><td>LONG</td><td>Size of segment in bytes</td></tr> |
| <tr><td>version</td><td>STRING</td><td>Version string (generally an ISO8601 timestamp corresponding to when the segment set was first started). Higher version means the more recently created segment. Version comparing is based on string comparison.</td></tr> |
| <tr><td>partition_num</td><td>LONG</td><td>Partition number (an integer, unique within a datasource+interval+version; may not necessarily be contiguous)</td></tr> |
| <tr><td>num_replicas</td><td>LONG</td><td>Number of replicas of this segment currently being served</td></tr> |
| <tr><td>num_rows</td><td>LONG</td><td>Number of rows in current segment, this value could be null if unknown to Broker at query time</td></tr> |
| <tr><td>is_published</td><td>LONG</td><td>Boolean is represented as long type where 1 = true, 0 = false. 1 represents this segment has been published to the metadata store with <code>used=1</code>. See the <a href="/docs/0.16.1-incubating/design/architecture.html#segment-lifecycle">Architecture page</a> for more details.</td></tr> |
| <tr><td>is_available</td><td>LONG</td><td>Boolean is represented as long type where 1 = true, 0 = false. 1 if this segment is currently being served by any process(Historical or realtime). See the <a href="/docs/0.16.1-incubating/design/architecture.html#segment-lifecycle">Architecture page</a> for more details.</td></tr> |
| <tr><td>is_realtime</td><td>LONG</td><td>Boolean is represented as long type where 1 = true, 0 = false. 1 if this segment is <em>only</em> served by realtime tasks, and 0 if any historical process is serving this segment.</td></tr> |
| <tr><td>is_overshadowed</td><td>LONG</td><td>Boolean is represented as long type where 1 = true, 0 = false. 1 if this segment is published and is <em>fully</em> overshadowed by some other published segments. Currently, is_overshadowed is always false for unpublished segments, although this may change in the future. You can filter for segments that "should be published" by filtering for <code>is_published = 1 AND is_overshadowed = 0</code>. Segments can briefly be both published and overshadowed if they were recently replaced, but have not been unpublished yet. See the <a href="/docs/0.16.1-incubating/design/architecture.html#segment-lifecycle">Architecture page</a> for more details.</td></tr> |
| <tr><td>payload</td><td>STRING</td><td>JSON-serialized data segment payload</td></tr> |
| </tbody> |
| </table> |
| <p>For example to retrieve all segments for datasource "wikipedia", use the query:</p> |
| <pre><code class="hljs css language-sql"><span class="hljs-keyword">SELECT</span> * <span class="hljs-keyword">FROM</span> sys.segments <span class="hljs-keyword">WHERE</span> datasource = <span class="hljs-string">'wikipedia'</span> |
| </code></pre> |
| <p>Another example to retrieve segments total_size, avg_size, avg_num_rows and num_segments per datasource:</p> |
| <pre><code class="hljs css language-sql"><span class="hljs-keyword">SELECT</span> |
| datasource, |
| <span class="hljs-keyword">SUM</span>(<span class="hljs-string">"size"</span>) <span class="hljs-keyword">AS</span> total_size, |
| <span class="hljs-keyword">CASE</span> <span class="hljs-keyword">WHEN</span> <span class="hljs-keyword">SUM</span>(<span class="hljs-string">"size"</span>) = <span class="hljs-number">0</span> <span class="hljs-keyword">THEN</span> <span class="hljs-number">0</span> <span class="hljs-keyword">ELSE</span> <span class="hljs-keyword">SUM</span>(<span class="hljs-string">"size"</span>) / (<span class="hljs-keyword">COUNT</span>(*) FILTER(<span class="hljs-keyword">WHERE</span> <span class="hljs-string">"size"</span> > <span class="hljs-number">0</span>)) <span class="hljs-keyword">END</span> <span class="hljs-keyword">AS</span> avg_size, |
| <span class="hljs-keyword">CASE</span> <span class="hljs-keyword">WHEN</span> <span class="hljs-keyword">SUM</span>(num_rows) = <span class="hljs-number">0</span> <span class="hljs-keyword">THEN</span> <span class="hljs-number">0</span> <span class="hljs-keyword">ELSE</span> <span class="hljs-keyword">SUM</span>(<span class="hljs-string">"num_rows"</span>) / (<span class="hljs-keyword">COUNT</span>(*) FILTER(<span class="hljs-keyword">WHERE</span> num_rows > <span class="hljs-number">0</span>)) <span class="hljs-keyword">END</span> <span class="hljs-keyword">AS</span> avg_num_rows, |
| <span class="hljs-keyword">COUNT</span>(*) <span class="hljs-keyword">AS</span> num_segments |
| <span class="hljs-keyword">FROM</span> sys.segments |
| <span class="hljs-keyword">GROUP</span> <span class="hljs-keyword">BY</span> <span class="hljs-number">1</span> |
| <span class="hljs-keyword">ORDER</span> <span class="hljs-keyword">BY</span> <span class="hljs-number">2</span> <span class="hljs-keyword">DESC</span> |
| </code></pre> |
| <p><em>Caveat:</em> Note that a segment can be served by more than one stream ingestion tasks or Historical processes, in that case it would have multiple replicas. These replicas are weakly consistent with each other when served by multiple ingestion tasks, until a segment is eventually served by a Historical, at that point the segment is immutable. Broker prefers to query a segment from Historical over an ingestion task. But if a segment has multiple realtime replicas, for e.g.. Kafka index tasks, and one task is slower than other, then the sys.segments query results can vary for the duration of the tasks because only one of the ingestion tasks is queried by the Broker and it is not guaranteed that the same task gets picked every time. The <code>num_rows</code> column of segments table can have inconsistent values during this period. There is an open <a href="https://github.com/apache/incubator-druid/issues/5915">issue</a> about this inconsistency with stream ingestion tasks.</p> |
| <h4><a class="anchor" aria-hidden="true" id="servers-table"></a><a href="#servers-table" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>SERVERS table</h4> |
| <p>Servers table lists all discovered servers in the cluster.</p> |
| <table> |
| <thead> |
| <tr><th>Column</th><th>Type</th><th>Notes</th></tr> |
| </thead> |
| <tbody> |
| <tr><td>server</td><td>STRING</td><td>Server name in the form host:port</td></tr> |
| <tr><td>host</td><td>STRING</td><td>Hostname of the server</td></tr> |
| <tr><td>plaintext_port</td><td>LONG</td><td>Unsecured port of the server, or -1 if plaintext traffic is disabled</td></tr> |
| <tr><td>tls_port</td><td>LONG</td><td>TLS port of the server, or -1 if TLS is disabled</td></tr> |
| <tr><td>server_type</td><td>STRING</td><td>Type of Druid service. Possible values include: COORDINATOR, OVERLORD, BROKER, ROUTER, HISTORICAL, MIDDLE_MANAGER or PEON.</td></tr> |
| <tr><td>tier</td><td>STRING</td><td>Distribution tier see <a href="../configuration/index.html#historical-general-configuration">druid.server.tier</a>. Only valid for HISTORICAL type, for other types it's null</td></tr> |
| <tr><td>current_size</td><td>LONG</td><td>Current size of segments in bytes on this server. Only valid for HISTORICAL type, for other types it's 0</td></tr> |
| <tr><td>max_size</td><td>LONG</td><td>Max size in bytes this server recommends to assign to segments see <a href="../configuration/index.html#historical-general-configuration">druid.server.maxSize</a>. Only valid for HISTORICAL type, for other types it's 0</td></tr> |
| </tbody> |
| </table> |
| <p>To retrieve information about all servers, use the query:</p> |
| <pre><code class="hljs css language-sql"><span class="hljs-keyword">SELECT</span> * <span class="hljs-keyword">FROM</span> sys.servers; |
| </code></pre> |
| <h4><a class="anchor" aria-hidden="true" id="server_segments-table"></a><a href="#server_segments-table" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>SERVER_SEGMENTS table</h4> |
| <p>SERVER_SEGMENTS is used to join servers with segments table</p> |
| <table> |
| <thead> |
| <tr><th>Column</th><th>Type</th><th>Notes</th></tr> |
| </thead> |
| <tbody> |
| <tr><td>server</td><td>STRING</td><td>Server name in format host:port (Primary key of <a href="#servers-table">servers table</a>)</td></tr> |
| <tr><td>segment_id</td><td>STRING</td><td>Segment identifier (Primary key of <a href="#segments-table">segments table</a>)</td></tr> |
| </tbody> |
| </table> |
| <p>JOIN between "servers" and "segments" can be used to query the number of segments for a specific datasource, |
| grouped by server, example query:</p> |
| <pre><code class="hljs css language-sql"><span class="hljs-keyword">SELECT</span> <span class="hljs-keyword">count</span>(segments.segment_id) <span class="hljs-keyword">as</span> num_segments <span class="hljs-keyword">from</span> sys.segments <span class="hljs-keyword">as</span> segments |
| <span class="hljs-keyword">INNER</span> <span class="hljs-keyword">JOIN</span> sys.server_segments <span class="hljs-keyword">as</span> server_segments |
| <span class="hljs-keyword">ON</span> segments.segment_id = server_segments.segment_id |
| <span class="hljs-keyword">INNER</span> <span class="hljs-keyword">JOIN</span> sys.servers <span class="hljs-keyword">as</span> servers |
| <span class="hljs-keyword">ON</span> servers.server = server_segments.server |
| <span class="hljs-keyword">WHERE</span> segments.datasource = <span class="hljs-string">'wikipedia'</span> |
| <span class="hljs-keyword">GROUP</span> <span class="hljs-keyword">BY</span> servers.server; |
| </code></pre> |
| <h4><a class="anchor" aria-hidden="true" id="tasks-table"></a><a href="#tasks-table" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>TASKS table</h4> |
| <p>The tasks table provides information about active and recently-completed indexing tasks. For more information |
| check out the documentation for <a href="../ingestion/tasks.html">ingestion tasks</a>.</p> |
| <table> |
| <thead> |
| <tr><th>Column</th><th>Type</th><th>Notes</th></tr> |
| </thead> |
| <tbody> |
| <tr><td>task_id</td><td>STRING</td><td>Unique task identifier</td></tr> |
| <tr><td>group_id</td><td>STRING</td><td>Task group ID for this task, the value depends on the task <code>type</code>. For example, for native index tasks, it's same as <code>task_id</code>, for sub tasks, this value is the parent task's ID</td></tr> |
| <tr><td>type</td><td>STRING</td><td>Task type, for example this value is "index" for indexing tasks. See <a href="../ingestion/tasks.html">tasks-overview</a></td></tr> |
| <tr><td>datasource</td><td>STRING</td><td>Datasource name being indexed</td></tr> |
| <tr><td>created_time</td><td>STRING</td><td>Timestamp in ISO8601 format corresponding to when the ingestion task was created. Note that this value is populated for completed and waiting tasks. For running and pending tasks this value is set to 1970-01-01T00:00:00Z</td></tr> |
| <tr><td>queue_insertion_time</td><td>STRING</td><td>Timestamp in ISO8601 format corresponding to when this task was added to the queue on the Overlord</td></tr> |
| <tr><td>status</td><td>STRING</td><td>Status of a task can be RUNNING, FAILED, SUCCESS</td></tr> |
| <tr><td>runner_status</td><td>STRING</td><td>Runner status of a completed task would be NONE, for in-progress tasks this can be RUNNING, WAITING, PENDING</td></tr> |
| <tr><td>duration</td><td>LONG</td><td>Time it took to finish the task in milliseconds, this value is present only for completed tasks</td></tr> |
| <tr><td>location</td><td>STRING</td><td>Server name where this task is running in the format host:port, this information is present only for RUNNING tasks</td></tr> |
| <tr><td>host</td><td>STRING</td><td>Hostname of the server where task is running</td></tr> |
| <tr><td>plaintext_port</td><td>LONG</td><td>Unsecured port of the server, or -1 if plaintext traffic is disabled</td></tr> |
| <tr><td>tls_port</td><td>LONG</td><td>TLS port of the server, or -1 if TLS is disabled</td></tr> |
| <tr><td>error_msg</td><td>STRING</td><td>Detailed error message in case of FAILED tasks</td></tr> |
| </tbody> |
| </table> |
| <p>For example, to retrieve tasks information filtered by status, use the query</p> |
| <pre><code class="hljs css language-sql"><span class="hljs-keyword">SELECT</span> * <span class="hljs-keyword">FROM</span> sys.tasks <span class="hljs-keyword">WHERE</span> <span class="hljs-keyword">status</span>=<span class="hljs-string">'FAILED'</span>; |
| </code></pre> |
| <p>Note that sys tables may not support all the Druid SQL Functions.</p> |
| <h2><a class="anchor" aria-hidden="true" id="server-configuration"></a><a href="#server-configuration" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Server configuration</h2> |
| <p>The Druid SQL server is configured through the following properties on the Broker.</p> |
| <table> |
| <thead> |
| <tr><th>Property</th><th>Description</th><th>Default</th></tr> |
| </thead> |
| <tbody> |
| <tr><td><code>druid.sql.enable</code></td><td>Whether to enable SQL at all, including background metadata fetching. If false, this overrides all other SQL-related properties and disables SQL metadata, serving, and planning completely.</td><td>true</td></tr> |
| <tr><td><code>druid.sql.avatica.enable</code></td><td>Whether to enable JDBC querying at <code>/druid/v2/sql/avatica/</code>.</td><td>true</td></tr> |
| <tr><td><code>druid.sql.avatica.maxConnections</code></td><td>Maximum number of open connections for the Avatica server. These are not HTTP connections, but are logical client connections that may span multiple HTTP connections.</td><td>25</td></tr> |
| <tr><td><code>druid.sql.avatica.maxRowsPerFrame</code></td><td>Maximum number of rows to return in a single JDBC frame. Setting this property to -1 indicates that no row limit should be applied. Clients can optionally specify a row limit in their requests; if a client specifies a row limit, the lesser value of the client-provided limit and <code>maxRowsPerFrame</code> will be used.</td><td>5,000</td></tr> |
| <tr><td><code>druid.sql.avatica.maxStatementsPerConnection</code></td><td>Maximum number of simultaneous open statements per Avatica client connection.</td><td>4</td></tr> |
| <tr><td><code>druid.sql.avatica.connectionIdleTimeout</code></td><td>Avatica client connection idle timeout.</td><td>PT5M</td></tr> |
| <tr><td><code>druid.sql.http.enable</code></td><td>Whether to enable JSON over HTTP querying at <code>/druid/v2/sql/</code>.</td><td>true</td></tr> |
| <tr><td><code>druid.sql.planner.maxQueryCount</code></td><td>Maximum number of queries to issue, including nested queries. Set to 1 to disable sub-queries, or set to 0 for unlimited.</td><td>8</td></tr> |
| <tr><td><code>druid.sql.planner.maxSemiJoinRowsInMemory</code></td><td>Maximum number of rows to keep in memory for executing two-stage semi-join queries like <code>SELECT * FROM Employee WHERE DeptName IN (SELECT DeptName FROM Dept)</code>.</td><td>100000</td></tr> |
| <tr><td><code>druid.sql.planner.maxTopNLimit</code></td><td>Maximum threshold for a <a href="/docs/0.16.1-incubating/querying/topnquery.html">TopN query</a>. Higher limits will be planned as <a href="/docs/0.16.1-incubating/querying/groupbyquery.html">GroupBy queries</a> instead.</td><td>100000</td></tr> |
| <tr><td><code>druid.sql.planner.metadataRefreshPeriod</code></td><td>Throttle for metadata refreshes.</td><td>PT1M</td></tr> |
| <tr><td><code>druid.sql.planner.useApproximateCountDistinct</code></td><td>Whether to use an approximate cardinality algorithm for <code>COUNT(DISTINCT foo)</code>.</td><td>true</td></tr> |
| <tr><td><code>druid.sql.planner.useApproximateTopN</code></td><td>Whether to use approximate <a href="../querying/topnquery.html">TopN queries</a> when a SQL query could be expressed as such. If false, exact <a href="../querying/groupbyquery.html">GroupBy queries</a> will be used instead.</td><td>true</td></tr> |
| <tr><td><code>druid.sql.planner.requireTimeCondition</code></td><td>Whether to require SQL to have filter conditions on __time column so that all generated native queries will have user specified intervals. If true, all queries without filter condition on __time column will fail</td><td>false</td></tr> |
| <tr><td><code>druid.sql.planner.sqlTimeZone</code></td><td>Sets the default time zone for the server, which will affect how time functions and timestamp literals behave. Should be a time zone name like "America/Los_Angeles" or offset like "-08:00".</td><td>UTC</td></tr> |
| <tr><td><code>druid.sql.planner.metadataSegmentCacheEnable</code></td><td>Whether to keep a cache of published segments in broker. If true, broker polls coordinator in background to get segments from metadata store and maintains a local cache. If false, coordinator's REST API will be invoked when broker needs published segments info.</td><td>false</td></tr> |
| <tr><td><code>druid.sql.planner.metadataSegmentPollPeriod</code></td><td>How often to poll coordinator for published segments list if <code>druid.sql.planner.metadataSegmentCacheEnable</code> is set to true. Poll period is in milliseconds.</td><td>60000</td></tr> |
| </tbody> |
| </table> |
| <h2><a class="anchor" aria-hidden="true" id="sql-metrics"></a><a href="#sql-metrics" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>SQL Metrics</h2> |
| <p>Broker will emit the following metrics for SQL.</p> |
| <table> |
| <thead> |
| <tr><th>Metric</th><th>Description</th><th>Dimensions</th><th>Normal Value</th></tr> |
| </thead> |
| <tbody> |
| <tr><td><code>sqlQuery/time</code></td><td>Milliseconds taken to complete a SQL.</td><td>id, nativeQueryIds, dataSource, remoteAddress, success.</td><td>< 1s</td></tr> |
| <tr><td><code>sqlQuery/bytes</code></td><td>number of bytes returned in SQL response.</td><td>id, nativeQueryIds, dataSource, remoteAddress, success.</td><td></td></tr> |
| </tbody> |
| </table> |
| <h2><a class="anchor" aria-hidden="true" id="authorization-permissions"></a><a href="#authorization-permissions" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Authorization Permissions</h2> |
| <p>Please see <a href="../development/extensions-core/druid-basic-security.html#sql-permissions">Defining SQL permissions</a> for information on what permissions are needed for making SQL queries in a secured cluster.</p> |
| </span></div></article></div><div class="docs-prevnext"><a class="docs-prev button" href="/docs/0.16.1-incubating/ingestion/faq.html"><span class="arrow-prev">← </span><span>Troubleshooting FAQ</span></a><a class="docs-next button" href="/docs/0.16.1-incubating/querying/querying.html"><span>Making native queries</span><span class="arrow-next"> →</span></a></div></div></div><nav class="onPageNav"><ul class="toc-headings"><li><a href="#query-syntax">Query syntax</a></li><li><a href="#data-types-and-casts">Data types and casts</a></li><li><a href="#built-in-functions">Built-in functions</a><ul class="toc-headings"><li><a href="#aggregation-functions">Aggregation functions</a></li><li><a href="#numeric-functions">Numeric functions</a></li><li><a href="#string-functions">String functions</a></li><li><a href="#time-functions">Time functions</a></li><li><a href="#ip-address-functions">IP address functions</a></li><li><a href="#comparison-operators">Comparison operators</a></li><li><a href="#multi-value-string-functions">Multi-value string functions</a></li><li><a href="#other-functions">Other functions</a></li><li><a href="#unsupported-features">Unsupported features</a></li></ul></li><li><a href="#query-execution">Query execution</a><ul class="toc-headings"><li><a href="#approximate-algorithms">Approximate algorithms</a></li></ul></li><li><a href="#client-apis">Client APIs</a><ul class="toc-headings"><li><a href="#json-over-http">JSON over HTTP</a></li><li><a href="#jdbc">JDBC</a></li><li><a href="#connection-context">Connection context</a></li></ul></li><li><a href="#metadata-tables">Metadata tables</a><ul class="toc-headings"><li><a href="#information-schema">INFORMATION SCHEMA</a></li><li><a href="#system-schema">SYSTEM SCHEMA</a></li></ul></li><li><a href="#server-configuration">Server configuration</a></li><li><a href="#sql-metrics">SQL Metrics</a></li><li><a href="#authorization-permissions">Authorization Permissions</a></li></ul></nav></div><footer class="nav-footer druid-footer" id="footer"><div class="container"><div class="text-center"><p><a href="/technology">Technology</a> · <a href="/use-cases">Use Cases</a> · <a href="/druid-powered">Powered by Druid</a> · <a href="/docs/0.16.1-incubating/latest">Docs</a> · <a href="/community/">Community</a> · <a href="/downloads.html">Download</a> · <a href="/faq">FAQ</a></p></div><div class="text-center"><a title="Join the user group" href="https://groups.google.com/forum/#!forum/druid-user" target="_blank"><span class="fa fa-comments"></span></a> · <a title="Follow Druid" href="https://twitter.com/druidio" target="_blank"><span class="fab fa-twitter"></span></a> · <a title="Download via Apache" href="https://www.apache.org/dyn/closer.cgi?path=/incubator/druid/{{ site.druid_versions[0].versions[0].version }}/apache-druid-{{ site.druid_versions[0].versions[0].version }}-bin.tar.gz" target="_blank"><span class="fas fa-feather"></span></a> · <a title="GitHub" href="https://github.com/apache/incubator-druid" target="_blank"><span class="fab fa-github"></span></a></div><div class="text-center license">Copyright © 2019 <a href="https://www.apache.org/" target="_blank">Apache Software Foundation</a>.<br/>Except where otherwise noted, licensed under <a rel="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA 4.0</a>.<br/>Apache Druid, Druid, and the Druid logo are either registered trademarks or trademarks of The Apache Software Foundation in the United States and other countries.</div></div></footer></div><script type="text/javascript" src="https://cdn.jsdelivr.net/docsearch.js/1/docsearch.min.js"></script><script> |
| document.addEventListener('keyup', function(e) { |
| if (e.target !== document.body) { |
| return; |
| } |
| // keyCode for '/' (slash) |
| if (e.keyCode === 191) { |
| const search = document.getElementById('search_input_react'); |
| search && search.focus(); |
| } |
| }); |
| </script><script> |
| var search = docsearch({ |
| |
| apiKey: '2de99082a9f38e49dfaa059bbe4c901d', |
| indexName: 'apache_druid', |
| inputSelector: '#search_input_react', |
| algoliaOptions: {"facetFilters":["language:en","version:../../incubator-druid-website-src/"]} |
| }); |
| </script></body></html> |
