| <!DOCTYPE html> |
| <html lang="en"> |
| <head> |
| <meta charset="UTF-8" /> |
| <meta name="viewport" content="width=device-width, initial-scale=1.0"> |
| <meta name="description" content="Apache Druid"> |
| <meta name="keywords" content="druid,kafka,database,analytics,streaming,real-time,real time,apache,open source"> |
| <meta name="author" content="Apache Software Foundation"> |
| |
| <title>Druid | Apache Druid (incubating) Expressions</title> |
| |
| <link rel="alternate" type="application/atom+xml" href="/feed"> |
| <link rel="shortcut icon" href="/img/favicon.png"> |
| |
| <link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.7.2/css/all.css" integrity="sha384-fnmOCqbTlWIlj8LyTjo7mOUStjsKC4pOpQbqyi7RrhN7udi9RwhKkMHpvLbHG9Sr" crossorigin="anonymous"> |
| |
| <link href='//fonts.googleapis.com/css?family=Open+Sans+Condensed:300,700,300italic|Open+Sans:300italic,400italic,600italic,400,300,600,700' rel='stylesheet' type='text/css'> |
| |
| <link rel="stylesheet" href="/css/bootstrap-pure.css?v=1.1"> |
| <link rel="stylesheet" href="/css/base.css?v=1.1"> |
| <link rel="stylesheet" href="/css/header.css?v=1.1"> |
| <link rel="stylesheet" href="/css/footer.css?v=1.1"> |
| <link rel="stylesheet" href="/css/syntax.css?v=1.1"> |
| <link rel="stylesheet" href="/css/docs.css?v=1.1"> |
| |
| <script> |
| (function() { |
| var cx = '000162378814775985090:molvbm0vggm'; |
| var gcse = document.createElement('script'); |
| gcse.type = 'text/javascript'; |
| gcse.async = true; |
| gcse.src = (document.location.protocol == 'https:' ? 'https:' : 'http:') + |
| '//cse.google.com/cse.js?cx=' + cx; |
| var s = document.getElementsByTagName('script')[0]; |
| s.parentNode.insertBefore(gcse, s); |
| })(); |
| </script> |
| |
| |
| </head> |
| |
| <body> |
| <!-- Start page_header include --> |
| <script src="//ajax.googleapis.com/ajax/libs/jquery/2.2.4/jquery.min.js"></script> |
| |
| <div class="top-navigator"> |
| <div class="container"> |
| <div class="left-cont"> |
| <a class="logo" href="/"><span class="druid-logo"></span></a> |
| </div> |
| <div class="right-cont"> |
| <ul class="links"> |
| <li class=""><a href="/technology">Technology</a></li> |
| <li class=""><a href="/use-cases">Use Cases</a></li> |
| <li class=""><a href="/druid-powered">Powered By</a></li> |
| <li class=""><a href="/docs/latest/design/">Docs</a></li> |
| <li class=""><a href="/community/">Community</a></li> |
| <li class="header-dropdown"> |
| <a>Apache</a> |
| <div class="header-dropdown-menu"> |
| <a href="https://www.apache.org/" target="_blank">Foundation</a> |
| <a href="https://www.apache.org/events/current-event" target="_blank">Events</a> |
| <a href="https://www.apache.org/licenses/" target="_blank">License</a> |
| <a href="https://www.apache.org/foundation/thanks.html" target="_blank">Thanks</a> |
| <a href="https://www.apache.org/security/" target="_blank">Security</a> |
| <a href="https://www.apache.org/foundation/sponsorship.html" target="_blank">Sponsorship</a> |
| </div> |
| </li> |
| <li class=" button-link"><a href="/downloads.html">Download</a></li> |
| </ul> |
| </div> |
| </div> |
| <div class="action-button menu-icon"> |
| <span class="fa fa-bars"></span> MENU |
| </div> |
| <div class="action-button menu-icon-close"> |
| <span class="fa fa-times"></span> MENU |
| </div> |
| </div> |
| |
| <script type="text/javascript"> |
| var $menu = $('.right-cont'); |
| var $menuIcon = $('.menu-icon'); |
| var $menuIconClose = $('.menu-icon-close'); |
| |
| function showMenu() { |
| $menu.fadeIn(100); |
| $menuIcon.fadeOut(100); |
| $menuIconClose.fadeIn(100); |
| } |
| |
| $menuIcon.click(showMenu); |
| |
| function hideMenu() { |
| $menu.fadeOut(100); |
| $menuIconClose.fadeOut(100); |
| $menuIcon.fadeIn(100); |
| } |
| |
| $menuIconClose.click(hideMenu); |
| |
| $(window).resize(function() { |
| if ($(window).width() >= 840) { |
| $menu.fadeIn(100); |
| $menuIcon.fadeOut(100); |
| $menuIconClose.fadeOut(100); |
| } |
| else { |
| $menu.fadeOut(100); |
| $menuIcon.fadeIn(100); |
| $menuIconClose.fadeOut(100); |
| } |
| }); |
| </script> |
| |
| <!-- Stop page_header include --> |
| |
| |
| <div class="container doc-container"> |
| |
| |
| |
| |
| <p> Looking for the <a href="/docs/0.23.0/">latest stable documentation</a>?</p> |
| |
| |
| <div class="row"> |
| <div class="col-md-9 doc-content"> |
| <p> |
| <a class="btn btn-default btn-xs visible-xs-inline-block visible-sm-inline-block" href="#toc">Table of Contents</a> |
| </p> |
| <!-- |
| ~ 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. |
| --> |
| |
| <h1 id="apache-druid-incubating-expressions">Apache Druid (incubating) Expressions</h1> |
| |
| <div class="note info"> |
| This feature is still experimental. It has not been optimized for performance yet, and its implementation is known to have significant inefficiencies. |
| </div> |
| |
| |
| <p>This expression language supports the following operators (listed in decreasing order of precedence).</p> |
| |
| <table><thead> |
| <tr> |
| <th>Operators</th> |
| <th>Description</th> |
| </tr> |
| </thead><tbody> |
| <tr> |
| <td>!, -</td> |
| <td>Unary NOT and Minus</td> |
| </tr> |
| <tr> |
| <td>^</td> |
| <td>Binary power op</td> |
| </tr> |
| <tr> |
| <td>*, /, %</td> |
| <td>Binary multiplicative</td> |
| </tr> |
| <tr> |
| <td>+, -</td> |
| <td>Binary additive</td> |
| </tr> |
| <tr> |
| <td><, <=, >, >=, ==, !=</td> |
| <td>Binary Comparison</td> |
| </tr> |
| <tr> |
| <td>&&, |</td> |
| <td>Binary Logical AND, OR</td> |
| </tr> |
| </tbody></table> |
| |
| <p>Long, double, and string data types are supported. If a number contains a dot, it is interpreted as a double, otherwise it is interpreted as a long. That means, always add a '.' to your number if you want it interpreted as a double value. String literals should be quoted by single quotation marks.</p> |
| |
| <p>Multi-value types are not fully supported yet. Expressions may behave inconsistently on multi-value types, and you |
| should not rely on the behavior in this case to stay the same in future releases.</p> |
| |
| <p>Expressions can contain variables. Variable names may contain letters, digits, '_' and '$'. Variable names must not begin with a digit. To escape other special characters, you can quote it with double quotation marks.</p> |
| |
| <p>For logical operators, a number is true if and only if it is positive (0 or negative value means false). For string type, it's the evaluation result of 'Boolean.valueOf(string)'.</p> |
| |
| <p>The following built-in functions are available.</p> |
| |
| <h2 id="general-functions">General functions</h2> |
| |
| <table><thead> |
| <tr> |
| <th>name</th> |
| <th>description</th> |
| </tr> |
| </thead><tbody> |
| <tr> |
| <td>cast</td> |
| <td>cast(expr,'LONG' or 'DOUBLE' or 'STRING') returns expr with specified type. exception can be thrown</td> |
| </tr> |
| <tr> |
| <td>if</td> |
| <td>if(predicate,then,else) returns 'then' if 'predicate' evaluates to a positive number, otherwise it returns 'else'</td> |
| </tr> |
| <tr> |
| <td>nvl</td> |
| <td>nvl(expr,expr-for-null) returns 'expr-for-null' if 'expr' is null (or empty string for string type)</td> |
| </tr> |
| <tr> |
| <td>like</td> |
| <td>like(expr, pattern[, escape]) is equivalent to SQL <code>expr LIKE pattern</code></td> |
| </tr> |
| <tr> |
| <td>case_searched</td> |
| <td>case_searched(expr1, result1, [[expr2, result2, ...], else-result])</td> |
| </tr> |
| <tr> |
| <td>case_simple</td> |
| <td>case_simple(expr, value1, result1, [[value2, result2, ...], else-result])</td> |
| </tr> |
| <tr> |
| <td>bloom_filter_test</td> |
| <td>bloom_filter_test(expr, filter) tests the value of 'expr' against 'filter', a bloom filter serialized as a base64 string. See <a href="../development/extensions-core/bloom-filter.html">bloom filter extension</a> documentation for additional details.</td> |
| </tr> |
| </tbody></table> |
| |
| <h2 id="string-functions">String functions</h2> |
| |
| <table><thead> |
| <tr> |
| <th>name</th> |
| <th>description</th> |
| </tr> |
| </thead><tbody> |
| <tr> |
| <td>concat</td> |
| <td>concat(expr, expr...) concatenate a list of strings</td> |
| </tr> |
| <tr> |
| <td>like</td> |
| <td>like(expr, pattern[, escape]) is equivalent to SQL <code>expr LIKE pattern</code></td> |
| </tr> |
| <tr> |
| <td>lookup</td> |
| <td>lookup(expr, lookup-name) looks up expr in a registered <a href="../querying/lookups.html">query-time lookup</a></td> |
| </tr> |
| <tr> |
| <td>regexp_extract</td> |
| <td>regexp_extract(expr, pattern[, index]) applies a regular expression pattern and extracts a capture group index, or null if there is no match. If index is unspecified or zero, returns the substring that matched the pattern.</td> |
| </tr> |
| <tr> |
| <td>replace</td> |
| <td>replace(expr, pattern, replacement) replaces pattern with replacement</td> |
| </tr> |
| <tr> |
| <td>substring</td> |
| <td>substring(expr, index, length) behaves like java.lang.String's substring</td> |
| </tr> |
| <tr> |
| <td>strlen</td> |
| <td>strlen(expr) returns length of a string in UTF-16 code units</td> |
| </tr> |
| <tr> |
| <td>strpos</td> |
| <td>strpos(haystack, needle[, fromIndex]) returns the position of the needle within the haystack, with indexes starting from 0. The search will begin at fromIndex, or 0 if fromIndex is not specified. If the needle is not found then the function returns -1.</td> |
| </tr> |
| <tr> |
| <td>trim</td> |
| <td>trim(expr[, chars]) remove leading and trailing characters from <code>expr</code> if they are present in <code>chars</code>. <code>chars</code> defaults to ' ' (space) if not provided.</td> |
| </tr> |
| <tr> |
| <td>ltrim</td> |
| <td>ltrim(expr[, chars]) remove leading characters from <code>expr</code> if they are present in <code>chars</code>. <code>chars</code> defaults to ' ' (space) if not provided.</td> |
| </tr> |
| <tr> |
| <td>rtrim</td> |
| <td>rtrim(expr[, chars]) remove trailing characters from <code>expr</code> if they are present in <code>chars</code>. <code>chars</code> defaults to ' ' (space) if not provided.</td> |
| </tr> |
| <tr> |
| <td>lower</td> |
| <td>lower(expr) converts a string to lowercase</td> |
| </tr> |
| <tr> |
| <td>upper</td> |
| <td>upper(expr) converts a string to uppercase</td> |
| </tr> |
| </tbody></table> |
| |
| <h2 id="time-functions">Time functions</h2> |
| |
| <table><thead> |
| <tr> |
| <th>name</th> |
| <th>description</th> |
| </tr> |
| </thead><tbody> |
| <tr> |
| <td>timestamp</td> |
| <td>timestamp(expr[,format-string]) parses string expr into date then returns milli-seconds from java epoch. without 'format-string' it's regarded as ISO datetime format</td> |
| </tr> |
| <tr> |
| <td>unix_timestamp</td> |
| <td>same with 'timestamp' function but returns seconds instead</td> |
| </tr> |
| <tr> |
| <td>timestamp_ceil</td> |
| <td>timestamp_ceil(expr, period, [origin, [timezone]]) 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".</td> |
| </tr> |
| <tr> |
| <td>timestamp_floor</td> |
| <td>timestamp_floor(expr, period, [origin, [timezone]]) 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".</td> |
| </tr> |
| <tr> |
| <td>timestamp_shift</td> |
| <td>timestamp_shift(expr, period, step, [timezone]) 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>timestamp_extract</td> |
| <td>timestamp_extract(expr, unit, [timezone]) extracts a time part from expr, returning it as a number. Unit can be EPOCH (number of seconds since 1970-01-01 00:00:00 UTC), 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"</td> |
| </tr> |
| <tr> |
| <td>timestamp_parse</td> |
| <td>timestamp_parse(string expr, [pattern, [timezone]]) 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>. If the pattern is not provided, this parses time strings in either ISO8601 or SQL format. 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 nulls.</td> |
| </tr> |
| <tr> |
| <td>timestamp_format</td> |
| <td>timestamp_format(expr, [pattern, [timezone]]) 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 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> |
| </tbody></table> |
| |
| <h2 id="math-functions">Math functions</h2> |
| |
| <p>See javadoc of java.lang.Math for detailed explanation for each function.</p> |
| |
| <table><thead> |
| <tr> |
| <th>name</th> |
| <th>description</th> |
| </tr> |
| </thead><tbody> |
| <tr> |
| <td>abs</td> |
| <td>abs(x) would return the absolute value of x</td> |
| </tr> |
| <tr> |
| <td>acos</td> |
| <td>acos(x) would return the arc cosine of x</td> |
| </tr> |
| <tr> |
| <td>asin</td> |
| <td>asin(x) would return the arc sine of x</td> |
| </tr> |
| <tr> |
| <td>atan</td> |
| <td>atan(x) would return the arc tangent of x</td> |
| </tr> |
| <tr> |
| <td>atan2</td> |
| <td>atan2(y, x) would return the angle theta from the conversion of rectangular coordinates (x, y) to polar * coordinates (r, theta)</td> |
| </tr> |
| <tr> |
| <td>cbrt</td> |
| <td>cbrt(x) would return the cube root of x</td> |
| </tr> |
| <tr> |
| <td>ceil</td> |
| <td>ceil(x) would return the smallest (closest to negative infinity) double value that is greater than or equal to x and is equal to a mathematical integer</td> |
| </tr> |
| <tr> |
| <td>copysign</td> |
| <td>copysign(x) would return the first floating-point argument with the sign of the second floating-point argument</td> |
| </tr> |
| <tr> |
| <td>cos</td> |
| <td>cos(x) would return the trigonometric cosine of x</td> |
| </tr> |
| <tr> |
| <td>cosh</td> |
| <td>cosh(x) would return the hyperbolic cosine of x</td> |
| </tr> |
| <tr> |
| <td>div</td> |
| <td>div(x,y) is integer division of x by y</td> |
| </tr> |
| <tr> |
| <td>exp</td> |
| <td>exp(x) would return Euler's number raised to the power of x</td> |
| </tr> |
| <tr> |
| <td>expm1</td> |
| <td>expm1(x) would return e^x-1</td> |
| </tr> |
| <tr> |
| <td>floor</td> |
| <td>floor(x) would return the largest (closest to positive infinity) double value that is less than or equal to x and is equal to a mathematical integer</td> |
| </tr> |
| <tr> |
| <td>getExponent</td> |
| <td>getExponent(x) would return the unbiased exponent used in the representation of x</td> |
| </tr> |
| <tr> |
| <td>hypot</td> |
| <td>hypot(x, y) would return sqrt(x^2+y^2) without intermediate overflow or underflow</td> |
| </tr> |
| <tr> |
| <td>log</td> |
| <td>log(x) would return the natural logarithm of x</td> |
| </tr> |
| <tr> |
| <td>log10</td> |
| <td>log10(x) would return the base 10 logarithm of x</td> |
| </tr> |
| <tr> |
| <td>log1p</td> |
| <td>log1p(x) would the natural logarithm of x + 1</td> |
| </tr> |
| <tr> |
| <td>max</td> |
| <td>max(x, y) would return the greater of two values</td> |
| </tr> |
| <tr> |
| <td>min</td> |
| <td>min(x, y) would return the smaller of two values</td> |
| </tr> |
| <tr> |
| <td>nextafter</td> |
| <td>nextafter(x, y) would return the floating-point number adjacent to the x in the direction of the y</td> |
| </tr> |
| <tr> |
| <td>nextUp</td> |
| <td>nextUp(x) would return the floating-point value adjacent to x in the direction of positive infinity</td> |
| </tr> |
| <tr> |
| <td>pow</td> |
| <td>pow(x, y) would return the value of the x raised to the power of y</td> |
| </tr> |
| <tr> |
| <td>remainder</td> |
| <td>remainder(x, y) would return the remainder operation on two arguments as prescribed by the IEEE 754 standard</td> |
| </tr> |
| <tr> |
| <td>rint</td> |
| <td>rint(x) would return value that is closest in value to x and is equal to a mathematical integer</td> |
| </tr> |
| <tr> |
| <td>round</td> |
| <td>round(x) would return the closest long value to x, with ties rounding up</td> |
| </tr> |
| <tr> |
| <td>scalb</td> |
| <td>scalb(d, sf) would return d * 2^sf rounded as if performed by a single correctly rounded floating-point multiply to a member of the double value set</td> |
| </tr> |
| <tr> |
| <td>signum</td> |
| <td>signum(x) would return the signum function of the argument x</td> |
| </tr> |
| <tr> |
| <td>sin</td> |
| <td>sin(x) would return the trigonometric sine of an angle x</td> |
| </tr> |
| <tr> |
| <td>sinh</td> |
| <td>sinh(x) would return the hyperbolic sine of x</td> |
| </tr> |
| <tr> |
| <td>sqrt</td> |
| <td>sqrt(x) would return the correctly rounded positive square root of x</td> |
| </tr> |
| <tr> |
| <td>tan</td> |
| <td>tan(x) would return the trigonometric tangent of an angle x</td> |
| </tr> |
| <tr> |
| <td>tanh</td> |
| <td>tanh(x) would return the hyperbolic tangent of x</td> |
| </tr> |
| <tr> |
| <td>todegrees</td> |
| <td>todegrees(x) converts an angle measured in radians to an approximately equivalent angle measured in degrees</td> |
| </tr> |
| <tr> |
| <td>toradians</td> |
| <td>toradians(x) converts an angle measured in degrees to an approximately equivalent angle measured in radians</td> |
| </tr> |
| <tr> |
| <td>ulp</td> |
| <td>ulp(x) would return the size of an ulp of the argument x</td> |
| </tr> |
| </tbody></table> |
| |
| </div> |
| <div class="col-md-3"> |
| <div class="searchbox"> |
| <gcse:searchbox-only></gcse:searchbox-only> |
| </div> |
| <div id="toc" class="nav toc hidden-print"> |
| </div> |
| </div> |
| </div> |
| </div> |
| |
| <!-- Start page_footer include --> |
| <footer class="druid-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/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="GitHub" href="https://github.com/apache/druid" target="_blank"><span class="fab fa-github"></span></a> |
| </div> |
| <div class="text-center license"> |
| Copyright © 2020 <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> |
| |
| <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> |
| <script> |
| function trackDownload(type, url) { |
| ga('send', 'event', 'download', type, url); |
| } |
| </script> |
| <script src="//code.jquery.com/jquery.min.js"></script> |
| <script src="//maxcdn.bootstrapcdn.com/bootstrap/3.2.0/js/bootstrap.min.js"></script> |
| <script src="/assets/js/druid.js"></script> |
| <!-- stop page_footer include --> |
| |
| |
| <script> |
| $(function() { |
| $(".toc").load("/docs/0.14.2-incubating/toc.html"); |
| |
| // There is no way to tell when .gsc-input will be async loaded into the page so just try to set a placeholder until it works |
| var tries = 0; |
| var timer = setInterval(function() { |
| tries++; |
| if (tries > 300) clearInterval(timer); |
| var searchInput = $('input.gsc-input'); |
| if (searchInput.length) { |
| searchInput.attr('placeholder', 'Search'); |
| clearInterval(timer); |
| } |
| }, 100); |
| }); |
| </script> |
| </body> |
| </html> |