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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="Normalizes dot field accesses that follow a subscript for DataFusion."><title>normalize_field_access_after_subscript in query::planner - 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 fn"><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="#">normalize_field_access_after_subscript</a></h2></rustdoc-topbar><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../../query/index.html">query</a><span class="version">1.3.0-alpha.1</span></h2></div><div class="sidebar-elems"><div id="rustdoc-modnav"><h2><a href="index.html">In query::<wbr>planner</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">planner</a></div><h1>Function <span class="fn">normalize_<wbr>field_<wbr>access_<wbr>after_<wbr>subscript</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/planner.rs.html#658-686">Source</a> </span></div><pre class="rust item-decl"><code>fn normalize_field_access_after_subscript(
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stmt: &mut Statement,
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normalize_ident: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.bool.html">bool</a>,
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)</code></pre><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Normalizes dot field accesses that follow a subscript for DataFusion.</p>
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<p>sqlparser represents <code>j.o.l[1].inner.l[2]</code> as a compound field access with
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the following access chain:</p>
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<div class="example-wrap"><pre class="language-text"><code>Dot(Identifier("o")),
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Dot(Identifier("l")),
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Subscript(1),
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Dot(Identifier("inner")),
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Dot(Identifier("l")),
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Subscript(2)</code></pre></div>
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<p>DataFusion first resolves the leading <code>j.o.l</code> through
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<code>JsonExprPlanner::plan_compound_identifier</code>, which produces an untyped
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<code>json_get</code> with path <code>o.l</code>. Before invoking <code>JsonExprPlanner::plan_field_access</code>,
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however, DataFusion eagerly converts every remaining access into a
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<code>GetFieldAccess</code>. It accepts string values but not [<code>SqlExpr::Identifier</code>]s
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in [<code>AccessExpr::Dot</code>] after a subscript. Without this normalization, that
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conversion fails at <code>.inner</code>, and <code>plan_field_access</code> is never called, even
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for the preceding <code>[1]</code>.</p>
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<p>This function converts dot identifiers after the first subscript into
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<code>Dot(Value(SingleQuotedString(...)))</code>, applying DataFusion’s identifier
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normalization before discarding whether each identifier was quoted. It
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changes neither the SQL text nor the dot accesses into subscript nodes: the
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resulting AST is conceptually <code>j.o.l[1].'inner'.'l'[2]</code>. DataFusion converts
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the string-valued dot accesses into named field accesses, which
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<code>plan_field_access</code> safely encodes as bracket members. It can then extend the
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JSON path to <code>o.l[1]["inner"]["l"][2]</code>.</p>
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<p>This behavior is unchanged in the latest upstream releases checked here:
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DataFusion 55.0.0 and sqlparser 0.62.0.</p>
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<p>TODO(LFC): Remove this workaround after upstream supports dot identifiers after subscripts.</p>
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</div></details></section></div></main></body></html> |