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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="API documentation for the Rust `plan_rewrite` mod in crate `query`."><title>query::range_select::plan_rewrite - 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-17e0aaed.css"><meta name="rustdoc-vars" data-root-path="../../../" data-static-root-path="../../../static.files/" data-current-crate="query" data-themes="" data-resource-suffix="" data-rustdoc-version="1.96.0-nightly (ac7f9ec7d 2026-03-20)" data-channel="nightly" data-search-js="search-63369b7b.js" data-stringdex-js="stringdex-2da4960a.js" data-settings-js="settings-170eb4bf.js" ><script src="../../../static.files/storage-41dd4d93.js"></script><script defer src="../sidebar-items.js"></script><script defer src="../../../static.files/main-5013f961.js"></script><noscript><link rel="stylesheet" href="../../../static.files/noscript-f7c3ffd8.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"><a class="skip-main-content" href="#main-content">Skip to main content</a><!--[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 plan_rewrite</a></h2></rustdoc-topbar><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../../../query/index.html">query</a><span class="version">1.0.0</span></h2></div><div class="sidebar-elems"><section id="rustdoc-toc"><h2 class="location"><a href="#">Module plan_<wbr>rewrite</a></h2><h3><a href="#macros">Module Items</a></h3><ul class="block"><li><a href="#macros" title="Macros">Macros</a></li><li><a href="#structs" title="Structs">Structs</a></li><li><a href="#functions" title="Functions">Functions</a></li></ul></section><div id="rustdoc-modnav"><h2><a href="../index.html">In query::<wbr>range_<wbr>select</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" tabindex="-1"><div class="main-heading"><div class="rustdoc-breadcrumbs"><a href="../../index.html">query</a>::<wbr><a href="../index.html">range_select</a></div><h1>Module <span>plan_<wbr>rewrite</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/query/range_select/plan_rewrite.rs.html#15-1177">Source</a> </span></div><h2 id="macros" class="section-header">Macros<a href="#macros" class="anchor">§</a></h2><dl class="item-table"><dt><a class="macro" href="macro.inconsistent_check.html" title="macro query::range_select::plan_rewrite::inconsistent_check">inconsistent_<wbr>check</a><span title="Restricted Visibility"> 🔒</span> </dt></dl><h2 id="structs" class="section-header">Structs<a href="#structs" class="anchor">§</a></h2><dl class="item-table"><dt><a class="struct" href="struct.RangeExprRewriter.html" title="struct query::range_select::plan_rewrite::RangeExprRewriter">Range<wbr>Expr<wbr>Rewriter</a></dt><dd><code>RangeExprRewriter</code> will recursively search certain <code>Expr</code>, find all <code>range_fn</code> scalar udf contained in <code>Expr</code>,
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and collect the information required by the RangeSelect query,
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and finally modify the <code>range_fn</code> scalar udf to an ordinary column field.</dd><dt><a class="struct" href="struct.RangePlanRewriter.html" title="struct query::range_select::plan_rewrite::RangePlanRewriter">Range<wbr>Plan<wbr>Rewriter</a></dt><dd>In order to implement RangeSelect query like <code>avg(field_0) RANGE '5m' FILL NULL</code>,
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All RangeSelect query items are converted into udf scalar function in sql parse stage, with format like <code>range_fn(avg(field_0), .....)</code>.
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<code>range_fn</code> contains all the parameters we need to execute RangeSelect.
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In order to correctly execute the query process of range select, we need to modify the query plan generated by datafusion.
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We need to recursively find the entire LogicalPlan, and find all <code>range_fn</code> scalar udf contained in the project plan,
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collecting info we need to generate RangeSelect Query LogicalPlan and rewrite th original LogicalPlan.</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.dispose_parse_error.html" title="fn query::range_select::plan_rewrite::dispose_parse_error">dispose_<wbr>parse_<wbr>error</a><span title="Restricted Visibility"> 🔒</span> </dt><dt><a class="fn" href="fn.evaluate_expr_to_millisecond.html" title="fn query::range_select::plan_rewrite::evaluate_expr_to_millisecond">evaluate_<wbr>expr_<wbr>to_<wbr>millisecond</a><span title="Restricted Visibility"> 🔒</span> </dt><dd>Evaluate a time calculation expr, case like:</dd><dt><a class="fn" href="fn.have_range_in_exprs.html" title="fn query::range_select::plan_rewrite::have_range_in_exprs">have_<wbr>range_<wbr>in_<wbr>exprs</a><span title="Restricted Visibility"> 🔒</span> </dt><dt><a class="fn" href="fn.interval_only_in_expr.html" title="fn query::range_select::plan_rewrite::interval_only_in_expr">interval_<wbr>only_<wbr>in_<wbr>expr</a><span title="Restricted Visibility"> 🔒</span> </dt><dt><a class="fn" href="fn.parse_align_to.html" title="fn query::range_select::plan_rewrite::parse_align_to">parse_<wbr>align_<wbr>to</a><span title="Restricted Visibility"> 🔒</span> </dt><dd>Parse the <code>align to</code> clause and return a UTC timestamp with unit of millisecond,
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which is used as the basis for dividing time slot during the align operation.</dd><dt><a class="fn" href="fn.parse_duration_expr.html" title="fn query::range_select::plan_rewrite::parse_duration_expr">parse_<wbr>duration_<wbr>expr</a><span title="Restricted Visibility"> 🔒</span> </dt><dd>Parse a duraion expr:</dd><dt><a class="fn" href="fn.parse_expr_list.html" title="fn query::range_select::plan_rewrite::parse_expr_list">parse_<wbr>expr_<wbr>list</a><span title="Restricted Visibility"> 🔒</span> </dt><dt><a class="fn" href="fn.parse_expr_to_string.html" title="fn query::range_select::plan_rewrite::parse_expr_to_string">parse_<wbr>expr_<wbr>to_<wbr>string</a><span title="Restricted Visibility"> 🔒</span> </dt><dt><a class="fn" href="fn.parse_str_expr.html" title="fn query::range_select::plan_rewrite::parse_str_expr">parse_<wbr>str_<wbr>expr</a><span title="Restricted Visibility"> 🔒</span> </dt></dl></section></div></main></body></html> |