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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 docsWrapper_BCFX"><button aria-label="Scroll back to top" class="clean-btn theme-back-to-top-button backToTopButton_sjWU" type="button"></button><div class="docPage__5DB"><main class="docMainContainer_gTbr docMainContainerEnhanced_Uz_u"><div class="container padding-top--md padding-bottom--lg"><div class="row"><div class="col docItemCol_VOVn"><div class="docItemContainer_Djhp"><article><div class="tocCollapsible_ETCw theme-doc-toc-mobile tocMobile_ITEo"><button type="button" class="clean-btn tocCollapsibleButton_TO0P">On this page</button></div><div class="theme-doc-markdown markdown"><header><h1>DataSketches HLL Sketch module</h1></header><p>This module provides Apache Druid aggregators for distinct counting based on HLL sketch from <a href="https://datasketches.apache.org/" target="_blank" rel="noopener noreferrer">Apache DataSketches</a> library. At ingestion time, this aggregator creates the HLL sketch objects to store in Druid segments. By default, Druid reads and merges sketches at query time. The default result is |
| the estimate of the number of distinct values presented to the sketch. You can also use post aggregators to produce a union of sketch columns in the same row. |
| You can use the HLL sketch aggregator on any column to estimate its cardinality.</p><p>To use this aggregator, make sure you <a href="/docs/27.0.0/configuration/extensions#loading-extensions">include</a> the extension in your config file:</p><div class="codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#bfc7d5;--prism-background-color:#292d3e"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-text codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#bfc7d5"><span class="token plain">druid.extensions.loadList=["druid-datasketches"]</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><p>For additional sketch types supported in Druid, see <a href="/docs/27.0.0/development/extensions-core/datasketches-extension">DataSketches extension</a>.</p><h2 class="anchor anchorWithStickyNavbar_LWe7" id="aggregators">Aggregators<a href="#aggregators" class="hash-link" aria-label="Direct link to Aggregators" title="Direct link to Aggregators"></a></h2><table><thead><tr><th>Property</th><th>Description</th><th>Required?</th></tr></thead><tbody><tr><td><code>type</code></td><td>Either <a href="#hllsketchbuild-aggregator"><code>HLLSketchBuild</code></a> or <a href="#hllsketchmerge-aggregator"><code>HLLSketchMerge</code></a>.</td><td>yes</td></tr><tr><td><code>name</code></td><td>String representing the output column to store sketch values.</td><td>yes</td></tr><tr><td><code>fieldName</code></td><td>The name of the input field.</td><td>yes</td></tr><tr><td><code>lgK</code></td><td>log2 of K that is the number of buckets in the sketch, parameter that controls the size and the accuracy. Must be between 4 and 21 inclusively.</td><td>no, defaults to <code>12</code></td></tr><tr><td><code>tgtHllType</code></td><td>The type of the target HLL sketch. Must be <code>HLL_4</code>, <code>HLL_6</code> or <code>HLL_8</code></td><td>no, defaults to <code>HLL_4</code></td></tr><tr><td><code>round</code></td><td>Round off values to whole numbers. Only affects query-time behavior and is ignored at ingestion-time.</td><td>no, defaults to <code>false</code></td></tr><tr><td><code>shouldFinalize</code></td><td>Return the final double type representing the estimate rather than the intermediate sketch type itself. In addition to controlling the finalization of this aggregator, you can control whether all aggregators are finalized with the query context parameters <a href="/docs/27.0.0/querying/query-context"><code>finalize</code></a> and <a href="/docs/27.0.0/querying/sql-query-context"><code>sqlFinalizeOuterSketches</code></a>.</td><td>no, defaults to <code>true</code></td></tr></tbody></table><div class="theme-admonition theme-admonition-info alert alert--info admonition_LlT9"><div class="admonitionHeading_tbUL"><span class="admonitionIcon_kALy"><svg viewBox="0 0 14 16"><path fill-rule="evenodd" d="M7 2.3c3.14 0 5.7 2.56 5.7 5.7s-2.56 5.7-5.7 5.7A5.71 5.71 0 0 1 1.3 8c0-3.14 2.56-5.7 5.7-5.7zM7 1C3.14 1 0 4.14 0 8s3.14 7 7 7 7-3.14 7-7-3.14-7-7-7zm1 3H6v5h2V4zm0 6H6v2h2v-2z"></path></svg></span>info</div><div class="admonitionContent_S0QG"><p> The default <code>lgK</code> value has proven to be sufficient for most use cases; expect only very negligible improvements in accuracy with <code>lgK</code> values over <code>16</code> in normal circumstances.</p></div></div><h3 class="anchor anchorWithStickyNavbar_LWe7" id="hllsketchbuild-aggregator">HLLSketchBuild aggregator<a href="#hllsketchbuild-aggregator" class="hash-link" aria-label="Direct link to HLLSketchBuild aggregator" title="Direct link to HLLSketchBuild aggregator"></a></h3><div class="codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#bfc7d5;--prism-background-color:#292d3e"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-text codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#bfc7d5"><span class="token plain">{</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "type": "HLLSketchBuild",</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "name": <output name>,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "fieldName": <metric name>,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "lgK": <size and accuracy parameter>,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "tgtHllType": <target HLL type>,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "round": <false | true></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> }</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><p>The <code>HLLSketchBuild</code> aggregator builds an HLL sketch object from the specified input column. When used during ingestion, Druid stores pre-generated HLL sketch objects in the datasource instead of the raw data from the input column. |
| When applied at query time on an existing dimension, you can use the resulting column as an intermediate dimension by the <a href="#post-aggregators">post-aggregators</a>.</p><div class="theme-admonition theme-admonition-info alert alert--info admonition_LlT9"><div class="admonitionHeading_tbUL"><span class="admonitionIcon_kALy"><svg viewBox="0 0 14 16"><path fill-rule="evenodd" d="M7 2.3c3.14 0 5.7 2.56 5.7 5.7s-2.56 5.7-5.7 5.7A5.71 5.71 0 0 1 1.3 8c0-3.14 2.56-5.7 5.7-5.7zM7 1C3.14 1 0 4.14 0 8s3.14 7 7 7 7-3.14 7-7-3.14-7-7-7zm1 3H6v5h2V4zm0 6H6v2h2v-2z"></path></svg></span>info</div><div class="admonitionContent_S0QG"><p> It is very common to use <code>HLLSketchBuild</code> in combination with <a href="/docs/27.0.0/ingestion/rollup">rollup</a> to create a <a href="/docs/27.0.0/ingestion/ingestion-spec#metricsspec">metric</a> on high-cardinality columns. In this example, a metric called <code>userid_hll</code> is included in the <code>metricsSpec</code>. This will perform a HLL sketch on the <code>userid</code> field at ingestion time, allowing for highly-performant approximate <code>COUNT DISTINCT</code> query operations and improving roll-up ratios when <code>userid</code> is then left out of the <code>dimensionsSpec</code>.</p><div class="codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#bfc7d5;--prism-background-color:#292d3e"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-text codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#bfc7d5"><span class="token plain">"metricsSpec": [</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> {</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "type": "HLLSketchBuild",</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "name": "userid_hll",</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "fieldName": "userid",</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "lgK": 12,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "tgtHllType": "HLL_4"</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> }</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain">]</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div></div><h3 class="anchor anchorWithStickyNavbar_LWe7" id="hllsketchmerge-aggregator">HLLSketchMerge aggregator<a href="#hllsketchmerge-aggregator" class="hash-link" aria-label="Direct link to HLLSketchMerge aggregator" title="Direct link to HLLSketchMerge aggregator"></a></h3><div class="codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#bfc7d5;--prism-background-color:#292d3e"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-text codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#bfc7d5"><span class="token plain">{</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "type": "HLLSketchMerge",</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "name": <output name>,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "fieldName": <metric name>,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "lgK": <size and accuracy parameter>,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "tgtHllType": <target HLL type>,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "round": <false | true></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain">}</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><p>You can use the <code>HLLSketchMerge</code> aggregator to ingest pre-generated sketches from an input dataset. For example, you can set up a batch processing job to generate the sketches before sending the data to Druid. You must serialize the sketches in the input dataset to Base64-encoded bytes. Then, specify <code>HLLSketchMerge</code> for the input column in the native ingestion <code>metricsSpec</code>.</p><h2 class="anchor anchorWithStickyNavbar_LWe7" id="post-aggregators">Post aggregators<a href="#post-aggregators" class="hash-link" aria-label="Direct link to Post aggregators" title="Direct link to Post aggregators"></a></h2><h3 class="anchor anchorWithStickyNavbar_LWe7" id="estimate">Estimate<a href="#estimate" class="hash-link" aria-label="Direct link to Estimate" title="Direct link to Estimate"></a></h3><p>Returns the distinct count estimate as a double.</p><div class="codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#bfc7d5;--prism-background-color:#292d3e"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-text codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#bfc7d5"><span class="token plain">{</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "type": "HLLSketchEstimate",</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "name": <output name>,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "field": <post aggregator that returns an HLL Sketch>,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "round": <if true, round the estimate. Default is false></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain">}</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><h3 class="anchor anchorWithStickyNavbar_LWe7" id="estimate-with-bounds">Estimate with bounds<a href="#estimate-with-bounds" class="hash-link" aria-label="Direct link to Estimate with bounds" title="Direct link to Estimate with bounds"></a></h3><p>Returns a distinct count estimate and error bounds from an HLL sketch. |
| The result will be an array containing three double values: estimate, lower bound and upper bound. |
| The bounds are provided at a given number of standard deviations (optional, defaults to 1). |
| This must be an integer value of 1, 2 or 3 corresponding to approximately 68.3%, 95.4% and 99.7% confidence intervals.</p><div class="codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#bfc7d5;--prism-background-color:#292d3e"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-text codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#bfc7d5"><span class="token plain">{</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "type": "HLLSketchEstimateWithBounds",</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "name": <output name>,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "field": <post aggregator that returns an HLL Sketch>,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "numStdDev": <number of standard deviations: 1 (default), 2 or 3></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain">}</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><h3 class="anchor anchorWithStickyNavbar_LWe7" id="union">Union<a href="#union" class="hash-link" aria-label="Direct link to Union" title="Direct link to Union"></a></h3><div class="codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#bfc7d5;--prism-background-color:#292d3e"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-text codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#bfc7d5"><span class="token plain">{</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "type": "HLLSketchUnion",</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "name": <output name>,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "fields": <array of post aggregators that return HLL sketches>,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "lgK": <log2 of K for the target sketch>,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "tgtHllType": <target HLL type></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain">}</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><h3 class="anchor anchorWithStickyNavbar_LWe7" id="sketch-to-string">Sketch to string<a href="#sketch-to-string" class="hash-link" aria-label="Direct link to Sketch to string" title="Direct link to Sketch to string"></a></h3><p>Human-readable sketch summary for debugging.</p><div class="codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#bfc7d5;--prism-background-color:#292d3e"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-text codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#bfc7d5"><span class="token plain">{</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "type": "HLLSketchToString",</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "name": <output name>,</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> "field": <post aggregator that returns an HLL Sketch></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain">}</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div></article><nav class="pagination-nav docusaurus-mt-lg" aria-label="Docs pages"></nav></div></div><div class="col col--3"><div class="tableOfContents_bqdL thin-scrollbar theme-doc-toc-desktop"><ul class="table-of-contents table-of-contents__left-border"><li><a href="#aggregators" class="table-of-contents__link toc-highlight">Aggregators</a><ul><li><a href="#hllsketchbuild-aggregator" class="table-of-contents__link toc-highlight">HLLSketchBuild aggregator</a></li><li><a href="#hllsketchmerge-aggregator" class="table-of-contents__link toc-highlight">HLLSketchMerge aggregator</a></li></ul></li><li><a href="#post-aggregators" class="table-of-contents__link toc-highlight">Post aggregators</a><ul><li><a href="#estimate" class="table-of-contents__link toc-highlight">Estimate</a></li><li><a href="#estimate-with-bounds" class="table-of-contents__link toc-highlight">Estimate with bounds</a></li><li><a href="#union" class="table-of-contents__link toc-highlight">Union</a></li><li><a href="#sketch-to-string" class="table-of-contents__link toc-highlight">Sketch to string</a></li></ul></li></ul></div></div></div></div></main></div></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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