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class="search-icon" tabindex="0"></span><input type="search" id="search_input_react" placeholder="Loading..." aria-label="Search" class="navbar__search-input search-bar" disabled=""></div></div></div></div><div role="presentation" class="navbar-sidebar__backdrop"></div></nav><div id="__docusaurus_skipToContent_fallback" class="main-wrapper mainWrapper_z2l0"><main class="container container--fluid margin-vert--lg"><div class="row mdxPageWrapper_j9I6"><div class="col col--8"><article><div class="theme-admonition theme-admonition-tip alert alert--success admonition_LlT9"><div class="admonitionHeading_tbUL"><span class="admonitionIcon_kALy"><svg viewBox="0 0 12 16"><path fill-rule="evenodd" d="M6.5 0C3.48 0 1 2.19 1 5c0 .92.55 2.25 1 3 1.34 2.25 1.78 2.78 2 4v1h5v-1c.22-1.22.66-1.75 2-4 .45-.75 1-2.08 1-3 0-2.81-2.48-5-5.5-5zm3.64 7.48c-.25.44-.47.8-.67 1.11-.86 1.41-1.25 2.06-1.45 3.23-.02.05-.02.11-.02.17H5c0-.06 0-.13-.02-.17-.2-1.17-.59-1.83-1.45-3.23-.2-.31-.42-.67-.67-1.11C2.44 6.78 2 5.65 2 5c0-2.2 2.02-4 4.5-4 1.22 0 2.36.42 3.22 1.19C10.55 2.94 11 3.94 11 5c0 .66-.44 1.78-.86 2.48zM4 14h5c-.23 1.14-1.3 2-2.5 2s-2.27-.86-2.5-2z"></path></svg></span>tip</div><div class="admonitionContent_S0QG"><p>Don't see your question here? <a href="/community/">Ask us</a></p></div></div><h3 class="anchor anchorWithStickyNavbar_LWe7" id="is-druid-a-data-warehouse-when-should-i-use-druid-over-redshiftbigquerysnowflake">Is Druid a data warehouse? When should I use Druid over Redshift/BigQuery/Snowflake?<a href="#is-druid-a-data-warehouse-when-should-i-use-druid-over-redshiftbigquerysnowflake" class="hash-link" aria-label="Direct link to Is Druid a data warehouse? When should I use Druid over Redshift/BigQuery/Snowflake?" title="Direct link to Is Druid a data warehouse? When should I use Druid over Redshift/BigQuery/Snowflake?"></a></h3><p>Apache Druid is a new type of database to power real-time analytic workloads for |
| event-driven data, and isn’t a traditional data warehouse. Although Druid |
| incorporates architecture ideas from data warehouses such as column-oriented |
| storage, Druid also incorporates designs from search systems and timeseries |
| databases. Druid's architecture is designed to handle many use cases that |
| traditional data warehouses cannot.</p><p>Druid offers the following advantages over traditional data warehouses:</p><ul><li>Much lower latency for OLAP-style queries</li><li>Much lower latency for data ingest (both streaming and batch)</li><li>Out-of-the-box integration with Apache Kafka, AWS Kinesis, HDFS, AWS S3, and more</li><li>Time-based partitioning, which enables performant time-based queries</li><li>Fast search and filter, for fast slice and dice</li><li>Minimal schema design and native support for semi-structured and nested data</li></ul><p>Consider using Druid to augment your data warehouse if your use case requires:</p><ul><li>Powering an user-facing application</li><li>Low-latency query response with high concurrency</li><li>Instant data visibility</li><li>Fast ad-hoc slice and dice</li><li>Streaming data</li></ul><p>To summarize, Druid shines when the use cases involves real-time analytics and |
| where the end-user (technical or not) wants to apply numerous queries in rapid |
| succession to explore or better understand data trends. </p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="is-druid-a-log-aggregationlog-search-system-when-should-i-use-druid-over-elasticsplunk">Is Druid a log aggregation/log search system? When should I use Druid over Elastic/Splunk?<a href="#is-druid-a-log-aggregationlog-search-system-when-should-i-use-druid-over-elasticsplunk" class="hash-link" aria-label="Direct link to Is Druid a log aggregation/log search system? When should I use Druid over Elastic/Splunk?" title="Direct link to Is Druid a log aggregation/log search system? When should I use Druid over Elastic/Splunk?"></a></h3><p>Druid uses inverted indexes (in particular, compressed bitmaps) for fast |
| searching and filtering, but it is not generally considered a search system. |
| While Druid contains many features commonly found in search systems, such as |
| the ability to stream in structured and semi-structured data and the ability to |
| search and filter the data, Druid isn’t commonly used to ingest text logs and |
| run full text search queries over the text logs. However, Druid is often used |
| to ingest and analyze semi-structured data such as JSON.</p><p>Druid at its core is an analytics engine and as such, it can support numerical |
| aggregations, groupBys (including multi-dimensional groupBys), and other |
| analytic workloads faster and more efficiently than search systems.</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="is-druid-a-timeseries-database-when-should-i-use-druid-over-influxdbopentsdbprometheus">Is Druid a timeseries database? When should I use Druid over InfluxDB/OpenTSDB/Prometheus?<a href="#is-druid-a-timeseries-database-when-should-i-use-druid-over-influxdbopentsdbprometheus" class="hash-link" aria-label="Direct link to Is Druid a timeseries database? When should I use Druid over InfluxDB/OpenTSDB/Prometheus?" title="Direct link to Is Druid a timeseries database? When should I use Druid over InfluxDB/OpenTSDB/Prometheus?"></a></h3><p>Druid does share some characteristics with timeseries databases, but also |
| combines ideas from analytic databases and search systems. Like in timeseries |
| databases, Druid is optimized for data where a timestamp is present. Druid |
| partitions data by time, and queries that include a time filter will be |
| significantly faster than those that do not. Aggregating metrics and filtering |
| on dimensions (which are roughly equivalent to TSDBs' tags) are also very fast when a |
| time filter is present. However, because Druid incorporates many architectural designs |
| from analytics databases and search systems, it can significantly |
| outperformance TSDBs when grouping, searching, and filtering on tags that are |
| not time, or when computing complex metrics such as histograms and quantiles.</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="does-druid-separate-storage-and-compute">Does Druid separate storage and compute?<a href="#does-druid-separate-storage-and-compute" class="hash-link" aria-label="Direct link to Does Druid separate storage and compute?" title="Direct link to Does Druid separate storage and compute?"></a></h3><p>Druid creates an indexed copy of raw data that is highly optimized for |
| analytic queries. Druid runs queries over this indexed data, called a <a href="/docs/latest/design/segments">'segment'</a> |
| in Druid, and does not pull raw data from an external storage system as needed |
| by queries. </p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="how-is-druid-deployed">How is Druid deployed?<a href="#how-is-druid-deployed" class="hash-link" aria-label="Direct link to How is Druid deployed?" title="Direct link to How is Druid deployed?"></a></h3><p>Druid can be deployed on commodity hardware in any *NIX based environment. |
| A Druid cluster consists of several different services, each designed to do a small set of things very well (ingestion, querying, coordination, etc). |
| Many of these services can be co-located and deployed together on the same hardware as described <a href="/docs/latest/tutorials/">here</a>.</p><p>Druid was designed for the cloud, and runs well in AWS, GCP, Azure, and other cloud environments.</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="where-does-druid-fit-in-my-big-data-stack">Where does Druid fit in my big data stack?<a href="#where-does-druid-fit-in-my-big-data-stack" class="hash-link" aria-label="Direct link to Where does Druid fit in my big data stack?" title="Direct link to Where does Druid fit in my big data stack?"></a></h3><p>Druid typically connects to a source of raw data such as a message bus such as Apache Kafka, or a filesystem such as HDFS. |
| Druid ingests an optimized, column-oriented, indexed copy of your data and serves analytics workloads on top of it.</p><p>A common streaming data oriented setup involving Druid looks like this: |
| Raw data → Kafka → Stream processor (optional, typically for ETL) → Kafka (optional) → Druid → Application/user</p><p>A common batch/static file oriented setup involving Druid looks like this: |
| Raw data → Kafka (optional) → HDFS → ETL process (optional) → Druid → Application/user</p><p>The same Druid cluster can serve both the streaming and batch path.</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="is-druid-in-memory">Is Druid in-memory?<a href="#is-druid-in-memory" class="hash-link" aria-label="Direct link to Is Druid in-memory?" title="Direct link to Is Druid in-memory?"></a></h3><p>The earliest iterations of Druid didn’t allow for data to be paged in from |
| and out to disk, so it was often called an “in-memory” database. As Druid |
| evolved, this limitation was removed. To provide a balance between hardware |
| cost and query performance, Druid leverages memory-mapping to page data between |
| disk and memory and extend the amount of data a single node can load up to the |
| size of its disks.</p><p>Individual Historicals can be configured with the maximum amount of data |
| they should be given. Coupled with the Coordinator’s ability to assign data to |
| different “tiers” based on different query requirements, Druid is essentially a |
| system that can be configured across a wide spectrum of performance |
| requirements. All data can be in memory and processed, or data can be heavily |
| over-committed compared to the amount of memory available. Druid can also |
| support complex configurations, such as configuring the most recent month of |
| data in memory, while everything else is over-committed.</p></article></div><div class="col col--2"><div class="tableOfContents_bqdL thin-scrollbar"><ul class="table-of-contents table-of-contents__left-border"><li><a href="#is-druid-a-data-warehouse-when-should-i-use-druid-over-redshiftbigquerysnowflake" class="table-of-contents__link toc-highlight">Is Druid a data warehouse? When should I use Druid over Redshift/BigQuery/Snowflake?</a></li><li><a href="#is-druid-a-log-aggregationlog-search-system-when-should-i-use-druid-over-elasticsplunk" class="table-of-contents__link toc-highlight">Is Druid a log aggregation/log search system? When should I use Druid over Elastic/Splunk?</a></li><li><a href="#is-druid-a-timeseries-database-when-should-i-use-druid-over-influxdbopentsdbprometheus" class="table-of-contents__link toc-highlight">Is Druid a timeseries database? When should I use Druid over InfluxDB/OpenTSDB/Prometheus?</a></li><li><a href="#does-druid-separate-storage-and-compute" class="table-of-contents__link toc-highlight">Does Druid separate storage and compute?</a></li><li><a href="#how-is-druid-deployed" class="table-of-contents__link toc-highlight">How is Druid deployed?</a></li><li><a href="#where-does-druid-fit-in-my-big-data-stack" class="table-of-contents__link toc-highlight">Where does Druid fit in my big data stack?</a></li><li><a href="#is-druid-in-memory" class="table-of-contents__link toc-highlight">Is Druid in-memory?</a></li></ul></div></div></div></main></div><footer class="footer"><div class="container container-fluid"><div class="footer__bottom text--center"><div class="margin-bottom--sm"><img src="/img/favicon.png" class="themedImage_ToTc themedImage--light_HNdA footer__logo"><img src="/img/favicon.png" class="themedImage_ToTc themedImage--dark_i4oU footer__logo"></div><div class="footer__copyright">Copyright © 2023 Apache Software Foundation. Except where otherwise noted, licensed under CC BY-SA 4.0. 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></div></footer></div> |
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