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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="Selects the SST files for a scan and, when requested, determines whether the selected files support an exact sequence-range scan."><title>exact_sequence_range in mito2::read::scan_region - 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-1ed95124.css"><meta name="rustdoc-vars" data-root-path="../../../" data-static-root-path="../../../static.files/" data-current-crate="mito2" data-themes="" data-resource-suffix="" data-rustdoc-version="1.98.1 (48a229cea 2026-09-01)" data-channel="1.98.1" data-search-js="search-9944d736.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-417ebf0a.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="#">exact_sequence_range</a></h2></rustdoc-topbar><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../../../mito2/index.html">mito2</a><span class="version">1.4.0-alpha.0</span></h2></div><div class="sidebar-elems"><div id="rustdoc-modnav"><h2><a href="index.html">In mito2::<wbr>read::<wbr>scan_<wbr>region</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">mito2</a>::<wbr><a href="../index.html">read</a>::<wbr><a href="index.html">scan_region</a></div><h1>Function <span class="fn">exact_<wbr>sequence_<wbr>range</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/mito2/read/scan_region.rs.html#1870-1949">Source</a> </span></div><pre class="rust item-decl"><code>pub(crate) fn exact_sequence_range(
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request: &ScanRequest,
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version: &<a class="struct" href="../../region/version/struct.Version.html" title="struct mito2::region::version::Version">Version</a>,
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) -> <a class="type" href="../../error/type.Result.html" title="type mito2::error::Result">Result</a><(<a class="struct" href="https://doc.rust-lang.org/1.98.1/alloc/vec/struct.Vec.html" title="struct alloc::vec::Vec">Vec</a><<a class="struct" href="../../sst/file/struct.FileHandle.html" title="struct mito2::sst::file::FileHandle">FileHandle</a>>, <a class="enum" href="https://doc.rust-lang.org/1.98.1/core/option/enum.Option.html" title="enum core::option::Option">Option</a><SequenceRange>)></code></pre><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Selects the SST files for a scan and, when requested, determines whether
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the selected files support an exact sequence-range scan.</p>
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<p>Files excluded by the request time range are not selected: <code>(C, H]</code> rows are
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a subset of the query’s time-range rows, so a time-pruned file cannot
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contribute a row to <code>(C, H]</code>.</p>
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<p>Unmarked local files use <code>FileMeta.sequence</code> as an admission barrier rather
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than a row maximum. Region edits allocate this barrier; compaction inherits
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the maximum input bound without assigning a new barrier. <code>C >= barrier</code>
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proves Flow has already consumed the entire file, so such a file is excluded
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before the capability check. An unknown bound cannot prove this exclusion.</p>
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<p>A foreign file is different: the parquet reader virtualizes every row to its
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target-local <code>FileMeta.sequence</code>. Consequently, a present sequence is the
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only trust requirement for a foreign file; its source marker is irrelevant.
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A foreign file without that barrier is retained as a failed-closed error so
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it cannot be mistaken for a local sequence domain. This check is performed
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even when another exact-range capability condition would return <code>None</code>.</p>
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</div></details></section></div></main></body></html> |