mirror of
https://github.com/GreptimeTeam/greptimedb.git
synced 2026-01-14 17:23:09 +00:00
18 lines
7.6 KiB
HTML
18 lines
7.6 KiB
HTML
<!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="Wrapper for making aggregate functions out of state/merge functions of original aggregate functions."><title>common_function::aggrs::aggr_wrapper - 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="common_function" 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 aggr_wrapper</a></h2></rustdoc-topbar><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../../../common_function/index.html">common_<wbr>function</a><span class="version">1.0.0-beta.3</span></h2></div><div class="sidebar-elems"><section id="rustdoc-toc"><h2 class="location"><a href="#">Module aggr_<wbr>wrapper</a></h2><h3><a href="#modules">Module Items</a></h3><ul class="block"><li><a href="#modules" title="Modules">Modules</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 common_<wbr>function::<wbr>aggrs</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">common_function</a>::<wbr><a href="../index.html">aggrs</a></div><h1>Module <span>aggr_<wbr>wrapper</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/common_function/aggrs/aggr_wrapper.rs.html#15-744">Source</a> </span></div><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Wrapper for making aggregate functions out of state/merge functions of original aggregate functions.</p>
|
||
<p>i.e. for a aggregate function <code>foo</code>, we will have a state function <code>foo_state</code> and a merge function <code>foo_merge</code>.</p>
|
||
<p><code>foo_state</code>’s input args is the same as <code>foo</code>’s, and its output is a state object.
|
||
Note that <code>foo_state</code> might have multiple output columns, so it’s a struct array
|
||
that each output column is a struct field.
|
||
<code>foo_merge</code>’s input arg is the same as <code>foo_state</code>’s output, and its output is the same as <code>foo</code>’s input.</p>
|
||
</div></details><h2 id="modules" class="section-header">Modules<a href="#modules" class="anchor">§</a></h2><dl class="item-table"><dt><a class="mod" href="fix_order/index.html" title="mod common_function::aggrs::aggr_wrapper::fix_order">fix_<wbr>order</a></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.MergeAccum.html" title="struct common_function::aggrs::aggr_wrapper::MergeAccum">Merge<wbr>Accum</a></dt><dd>The merge accumulator, which modify <code>update_batch</code>’s behavior to accept one struct array which
|
||
include the state fields of original aggregate function, and merge said states into original accumulator
|
||
the output is the same as original aggregate function</dd><dt><a class="struct" href="struct.MergeWrapper.html" title="struct common_function::aggrs::aggr_wrapper::MergeWrapper">Merge<wbr>Wrapper</a></dt><dd>TODO(discord9): mark this function as non-ser/de able</dd><dt><a class="struct" href="struct.StateAccum.html" title="struct common_function::aggrs::aggr_wrapper::StateAccum">State<wbr>Accum</a></dt><dd>The wrapper’s input is the same as the original aggregate function’s input,
|
||
and the output is the state function’s output.</dd><dt><a class="struct" href="struct.StateMergeHelper.html" title="struct common_function::aggrs::aggr_wrapper::StateMergeHelper">State<wbr>Merge<wbr>Helper</a></dt><dd>A wrapper to make an aggregate function out of the state and merge functions of the original aggregate function.
|
||
It contains the original aggregate function, the state functions, and the merge function.</dd><dt><a class="struct" href="struct.StateWrapper.html" title="struct common_function::aggrs::aggr_wrapper::StateWrapper">State<wbr>Wrapper</a></dt><dd>Wrapper to make an aggregate function out of a state function.</dd><dt><a class="struct" href="struct.StepAggrPlan.html" title="struct common_function::aggrs::aggr_wrapper::StepAggrPlan">Step<wbr>Aggr<wbr>Plan</a></dt><dd>A struct to hold the two aggregate plans, one for the state function(lower) and one for the merge function(upper).</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.aggr_merge_func_name.html" title="fn common_function::aggrs::aggr_wrapper::aggr_merge_func_name">aggr_<wbr>merge_<wbr>func_<wbr>name</a></dt><dd>Returns the name of the merge function for the given aggregate function name.
|
||
The merge function is used to merge the states of the state functions.
|
||
The merge function’s name is in the format `__<aggr_name>_merge</dd><dt><a class="fn" href="fn.aggr_state_func_name.html" title="fn common_function::aggrs::aggr_wrapper::aggr_state_func_name">aggr_<wbr>state_<wbr>func_<wbr>name</a></dt><dd>Returns the name of the state function for the given aggregate function name.
|
||
The state function is used to compute the state of the aggregate function.
|
||
The state function’s name is in the format `__<aggr_name>_state</dd><dt><a class="fn" href="fn.get_aggr_func.html" title="fn common_function::aggrs::aggr_wrapper::get_aggr_func">get_<wbr>aggr_<wbr>func</a></dt><dt><a class="fn" href="fn.is_all_aggr_exprs_steppable.html" title="fn common_function::aggrs::aggr_wrapper::is_all_aggr_exprs_steppable">is_<wbr>all_<wbr>aggr_<wbr>exprs_<wbr>steppable</a></dt><dd>Check if the given aggregate expression is steppable.
|
||
As in if it can be split into multiple steps:
|
||
i.e. on datanode first call <code>state(input)</code> then
|
||
on frontend call <code>calc(merge(state))</code> to get the final result.</dd></dl></section></div></main></body></html> |