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<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Accumulators for aggregate functions that’s is accumulatable. i.e. sum/count"><title>flow::expr::relation::accum - Rust</title><script>if(window.location.protocol!=="file:")document.head.insertAdjacentHTML("beforeend","SourceSerif4-Regular-6b053e98.ttf.woff2,FiraSans-Italic-81dc35de.woff2,FiraSans-Regular-0fe48ade.woff2,FiraSans-MediumItalic-ccf7e434.woff2,FiraSans-Medium-e1aa3f0a.woff2,SourceCodePro-Regular-8badfe75.ttf.woff2,SourceCodePro-Semibold-aa29a496.ttf.woff2".split(",").map(f=>`<link rel="preload" as="font" type="font/woff2"href="../../../../static.files/${f}">`).join(""))</script><link rel="stylesheet" href="../../../../static.files/normalize-9960930a.css"><link rel="stylesheet" href="../../../../static.files/rustdoc-e56847b5.css"><meta name="rustdoc-vars" data-root-path="../../../../" data-static-root-path="../../../../static.files/" data-current-crate="flow" data-themes="" data-resource-suffix="" data-rustdoc-version="1.92.0-nightly (fa3155a64 2025-09-30)" data-channel="nightly" data-search-js="search-e256b49e.js" data-stringdex-js="stringdex-828709d0.js" data-settings-js="settings-c38705f0.js" ><script src="../../../../static.files/storage-e2aeef58.js"></script><script defer src="../sidebar-items.js"></script><script defer src="../../../../static.files/main-ce535bd0.js"></script><noscript><link rel="stylesheet" href="../../../../static.files/noscript-263c88ec.css"></noscript><link rel="alternate icon" type="image/png" href="../../../../static.files/favicon-32x32-eab170b8.png"><link rel="icon" type="image/svg+xml" href="../../../../static.files/favicon-044be391.svg"></head><body class="rustdoc mod"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><rustdoc-topbar><h2><a href="#">Module accum</a></h2></rustdoc-topbar><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../../../../flow/index.html">flow</a><span class="version">1.0.0-rc.2</span></h2></div><div class="sidebar-elems"><section id="rustdoc-toc"><h2 class="location"><a href="#">Module accum</a></h2><h3><a href="#structs">Module Items</a></h3><ul class="block"><li><a href="#structs" title="Structs">Structs</a></li><li><a href="#enums" title="Enums">Enums</a></li><li><a href="#traits" title="Traits">Traits</a></li><li><a href="#functions" title="Functions">Functions</a></li></ul></section><div id="rustdoc-modnav"><h2><a href="../index.html">In flow::<wbr>expr::<wbr>relation</a></h2></div></div></nav><div class="sidebar-resizer" title="Drag to resize sidebar"></div><main><div class="width-limiter"><section id="main-content" class="content"><div class="main-heading"><div class="rustdoc-breadcrumbs"><a href="../../../index.html">flow</a>::<wbr><a href="../../index.html">expr</a>::<wbr><a href="../index.html">relation</a></div><h1>Module <span>accum</span> <button id="copy-path" title="Copy item path to clipboard">Copy item path</button></h1><rustdoc-toolbar></rustdoc-toolbar><span class="sub-heading"><a class="src" href="../../../../src/flow/expr/relation/accum.rs.html#15-1052">Source</a> </span></div><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Accumulators for aggregate functions that’s is accumulatable. i.e. sum/count</p>
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<p>Accumulator will only be restore from row and being updated every time dataflow need process a new batch of rows.
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So the overhead is acceptable.</p>
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<p>Currently support sum, count, any, all and min/max(with one caveat that min/max can’t support delete with aggregate).
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TODO: think of better ways to not ser/de every time a accum needed to be updated, since it’s in a tight loop</p>
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</div></details><h2 id="structs" class="section-header">Structs<a href="#structs" class="anchor">§</a></h2><dl class="item-table"><dt><a class="struct" href="struct.Bool.html" title="struct flow::expr::relation::accum::Bool">Bool</a></dt><dd>Bool accumulator, used for <code>Any</code> <code>All</code> <code>Max/MinBool</code></dd><dt><a class="struct" href="struct.Float.html" title="struct flow::expr::relation::accum::Float">Float</a></dt><dd>Accumulates float values for sum over floating numbers.</dd><dt><a class="struct" href="struct.OrdValue.html" title="struct flow::expr::relation::accum::OrdValue">OrdValue</a></dt><dd>Accumulates a single <code>Ord</code>ed <code>Value</code>, useful for min/max aggregations.</dd><dt><a class="struct" href="struct.SimpleNumber.html" title="struct flow::expr::relation::accum::SimpleNumber">Simple<wbr>Number</a></dt><dd>Accumulates simple numeric values for sum over integer.</dd></dl><h2 id="enums" class="section-header">Enums<a href="#enums" class="anchor">§</a></h2><dl class="item-table"><dt><a class="enum" href="enum.Accum.html" title="enum flow::expr::relation::accum::Accum">Accum</a></dt><dd>Accumulates values for the various types of accumulable aggregations.</dd></dl><h2 id="traits" class="section-header">Traits<a href="#traits" class="anchor">§</a></h2><dl class="item-table"><dt><a class="trait" href="trait.Accumulator.html" title="trait flow::expr::relation::accum::Accumulator">Accumulator</a></dt><dd>Accumulates values for the various types of accumulable aggregations.</dd></dl><h2 id="functions" class="section-header">Functions<a href="#functions" class="anchor">§</a></h2><dl class="item-table"><dt><a class="fn" href="fn.err_try_from_val.html" title="fn flow::expr::relation::accum::err_try_from_val">err_<wbr>try_<wbr>from_<wbr>val</a><span title="Restricted Visibility"> 🔒</span> </dt><dt><a class="fn" href="fn.fail_accum.html" title="fn flow::expr::relation::accum::fail_accum">fail_<wbr>accum</a><span title="Restricted Visibility"> 🔒</span> </dt><dt><a class="fn" href="fn.ty_eq_without_precision.html" title="fn flow::expr::relation::accum::ty_eq_without_precision">ty_<wbr>eq_<wbr>without_<wbr>precision</a><span title="Restricted Visibility"> 🔒</span> </dt><dd>compare type while ignore their precision, including <code>TimeStamp</code>, <code>Time</code>,
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<code>Duration</code>, <code>Interval</code></dd></dl></section></div></main></body></html> |