342/optimizer.html


<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <meta charset="utf-8" />
  <meta name="viewport" content="width=device-width,initial-scale=1">
  <meta http-equiv="x-ua-compatible" content="ie=edge">
  <meta name="lang:clipboard.copy" content="Copy to clipboard">
  <meta name="lang:clipboard.copied" content="Copied to clipboard">
  <meta name="lang:search.language" content="en">
  <meta name="lang:search.pipeline.stopwords" content="True">
  <meta name="lang:search.pipeline.trimmer" content="True">
  <meta name="lang:search.result.none" content="No matching documents">
  <meta name="lang:search.result.one" content="1 matching document">
  <meta name="lang:search.result.other" content="# matching documents">
  <meta name="lang:search.tokenizer" content="[\s\-]+">

  
    <link href="https://fonts.gstatic.com/" rel="preconnect" crossorigin>
    <link href="https://fonts.googleapis.com/css?family=Roboto+Mono:400,500,700|Roboto:300,400,400i,700&display=fallback" rel="stylesheet">

    <style>
      body,
      input {
        font-family: "Roboto", "Helvetica Neue", Helvetica, Arial, sans-serif
      }

      code,
      kbd,
      pre {
        font-family: "Roboto Mono", "Courier New", Courier, monospace
      }
    </style>
  

  <link rel="stylesheet" href="_static/stylesheets/application.css"/>
  <link rel="stylesheet" href="_static/stylesheets/application-palette.css"/>
  <link rel="stylesheet" href="_static/stylesheets/application-fixes.css"/>
  
  <link rel="stylesheet" href="_static/fonts/material-icons.css"/>
  
  <meta name="theme-color" content="2196f3">
  <script src="_static/javascripts/modernizr.js"></script>
  
  
    <title>Query Optimizer &#8212; Presto 342 Documentation</title>
    <link rel="stylesheet" href="_static/material.css" type="text/css" />
    <link rel="stylesheet" href="_static/pygments.css" type="text/css" />
    <link rel="stylesheet" type="text/css" href="_static/presto.css" />
    <script id="documentation_options" data-url_root="./" src="_static/documentation_options.js"></script>
    <script src="_static/jquery.js"></script>
    <script src="_static/underscore.js"></script>
    <script src="_static/doctools.js"></script>
    <script src="_static/language_data.js"></script>
    <link rel="index" title="Index" href="genindex.html" />
    <link rel="search" title="Search" href="search.html" />
    <link rel="next" title="Table Statistics" href="optimizer/statistics.html" />
    <link rel="prev" title="Distributed Sort" href="admin/dist-sort.html" />
  
   
    <script async src="https://www.googletagmanager.com/gtag/js?id=UA-133457846-1"></script>
    <script>
      window.dataLayer = window.dataLayer || [];
      function gtag(){dataLayer.push(arguments);}
      gtag('js', new Date());
      gtag('config', 'UA-133457846-1');
    </script>
  </head>
  <body dir=ltr
        data-md-color-primary=blue-grey data-md-color-accent=light-blue>
  
  <svg class="md-svg">
    <defs data-children-count="0">
      
      <svg xmlns="http://www.w3.org/2000/svg" width="416" height="448" viewBox="0 0 416 448" id="__github"><path fill="currentColor" d="M160 304q0 10-3.125 20.5t-10.75 19T128 352t-18.125-8.5-10.75-19T96 304t3.125-20.5 10.75-19T128 256t18.125 8.5 10.75 19T160 304zm160 0q0 10-3.125 20.5t-10.75 19T288 352t-18.125-8.5-10.75-19T256 304t3.125-20.5 10.75-19T288 256t18.125 8.5 10.75 19T320 304zm40 0q0-30-17.25-51T296 232q-10.25 0-48.75 5.25Q229.5 240 208 240t-39.25-2.75Q130.75 232 120 232q-29.5 0-46.75 21T56 304q0 22 8 38.375t20.25 25.75 30.5 15 35 7.375 37.25 1.75h42q20.5 0 37.25-1.75t35-7.375 30.5-15 20.25-25.75T360 304zm56-44q0 51.75-15.25 82.75-9.5 19.25-26.375 33.25t-35.25 21.5-42.5 11.875-42.875 5.5T212 416q-19.5 0-35.5-.75t-36.875-3.125-38.125-7.5-34.25-12.875T37 371.5t-21.5-28.75Q0 312 0 260q0-59.25 34-99-6.75-20.5-6.75-42.5 0-29 12.75-54.5 27 0 47.5 9.875t47.25 30.875Q171.5 96 212 96q37 0 70 8 26.25-20.5 46.75-30.25T376 64q12.75 25.5 12.75 54.5 0 21.75-6.75 42 34 40 34 99.5z"/></svg>
      
    </defs>
  </svg>
  
  <input class="md-toggle" data-md-toggle="drawer" type="checkbox" id="__drawer">
  <input class="md-toggle" data-md-toggle="search" type="checkbox" id="__search">
  <label class="md-overlay" data-md-component="overlay" for="__drawer"></label>
  <a href="#optimizer" tabindex="1" class="md-skip"> Skip to content </a>
  <header class="md-header" data-md-component="header">
  <nav class="md-header-nav md-grid">
    <div class="md-flex navheader">
      <div class="md-flex__cell md-flex__cell--shrink">
        <a href="index.html" title="Presto 342 Documentation"
           class="md-header-nav__button md-logo">
          
              <img src="_static/presto.svg" height="26"
                   alt="Presto 342 Documentation logo">
          
        </a>
      </div>
      <div class="md-flex__cell md-flex__cell--shrink">
        <label class="md-icon md-icon--menu md-header-nav__button" for="__drawer"></label>
      </div>
      <div class="md-flex__cell md-flex__cell--stretch">
        <div class="md-flex__ellipsis md-header-nav__title" data-md-component="title">
          <span class="md-header-nav__topic">Presto 342 Documentation</span>
          <span class="md-header-nav__topic"> Query Optimizer </span>
        </div>
      </div>
      <div class="md-flex__cell md-flex__cell--shrink">
        <label class="md-icon md-icon--search md-header-nav__button" for="__search"></label>
        
<div class="md-search" data-md-component="search" role="dialog">
  <label class="md-search__overlay" for="__search"></label>
  <div class="md-search__inner" role="search">
    <form class="md-search__form" action="search.html" method="GET" name="search">
      <input type="text" class="md-search__input" name="q" placeholder="Search"
             autocapitalize="off" autocomplete="off" spellcheck="false"
             data-md-component="query" data-md-state="active">
      <label class="md-icon md-search__icon" for="__search"></label>
      <button type="reset" class="md-icon md-search__icon" data-md-component="reset" tabindex="-1">
        &#xE5CD;
      </button>
    </form>
    <div class="md-search__output">
      <div class="md-search__scrollwrap" data-md-scrollfix>
        <div class="md-search-result" data-md-component="result">
          <div class="md-search-result__meta">
            Type to start searching
          </div>
          <ol class="md-search-result__list"></ol>
        </div>
      </div>
    </div>
  </div>
</div>

      </div>
      
        <div class="md-flex__cell md-flex__cell--shrink">
          <div class="md-header-nav__source">
            <a href="https://github.com/prestosql/presto" title="Go to repository" class="md-source" data-md-source="github">

    <div class="md-source__icon">
      <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 24 24" width="28" height="28">
        <use xlink:href="#__github" width="24" height="24"></use>
      </svg>
    </div>
  
  <div class="md-source__repository">
    Presto
  </div>
</a>
          </div>
        </div>
      
      
  <script src="_static/javascripts/version_dropdown.js"></script>
  <script>
    var json_loc = "../versions.json",
        target_loc = "../",
        text = "Versions";
    $( document ).ready( add_version_dropdown(json_loc, target_loc, text));
  </script>
  

    </div>
  </nav>
</header>

  
  <div class="md-container">
    
    
    <!-- empty -->
    <main class="md-main">
      <div class="md-main__inner md-grid" data-md-component="container">
        
          <div class="md-sidebar md-sidebar--primary" data-md-component="navigation">
            <div class="md-sidebar__scrollwrap">
              <div class="md-sidebar__inner">
                <nav class="md-nav md-nav--primary" data-md-level="0">
  <label class="md-nav__title md-nav__title--site" for="__drawer">
    <a href="index.html" title="Presto 342 Documentation" class="md-nav__button md-logo">
      
        <img src="_static/presto.svg" alt=" logo" width="48" height="48">
      
    </a>
    <a href="index.html"
       title="Presto 342 Documentation">Presto 342 Documentation</a>
  </label>
    <div class="md-nav__source">
      <a href="https://github.com/prestosql/presto" title="Go to repository" class="md-source" data-md-source="github">

    <div class="md-source__icon">
      <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 24 24" width="28" height="28">
        <use xlink:href="#__github" width="24" height="24"></use>
      </svg>
    </div>
  
  <div class="md-source__repository">
    Presto
  </div>
</a>
    </div>
  
  
  <ul class="md-nav__list">
    <li class="md-nav__item">
    
    
      <a href="overview.html" class="md-nav__link">Overview</a>
      
    
    </li>
    <li class="md-nav__item">
    
    
      <a href="installation.html" class="md-nav__link">Installation</a>
      
    
    </li>
    <li class="md-nav__item">
    
    
      <a href="client.html" class="md-nav__link">Clients</a>
      
    
    </li>
    <li class="md-nav__item">
    
    
      <a href="security.html" class="md-nav__link">Security</a>
      
    
    </li>
    <li class="md-nav__item">
    
    
      <a href="admin.html" class="md-nav__link">Administration</a>
      
    
    </li>
    <li class="md-nav__item">
    
    
    <input class="md-toggle md-nav__toggle" data-md-toggle="toc" type="checkbox" id="__toc">
    <label class="md-nav__link md-nav__link--active" for="__toc"> Query Optimizer </label>
    
      <a href="#" class="md-nav__link md-nav__link--active">Query Optimizer</a>
      
        
<nav class="md-nav md-nav--secondary">
    <ul class="md-nav__list" data-md-scrollfix="">
    </ul>
</nav>
      <ul class="md-nav__list"> 
    <li class="md-nav__item">
    
    
      <a href="optimizer/statistics.html" class="md-nav__link">Table Statistics</a>
      
    
    </li>
    <li class="md-nav__item">
    
    
      <a href="optimizer/cost-in-explain.html" class="md-nav__link">Cost in EXPLAIN</a>
      
    
    </li>
    <li class="md-nav__item">
    
    
      <a href="optimizer/cost-based-optimizations.html" class="md-nav__link">Cost based optimizations</a>
      
    
    </li>
    <li class="md-nav__item">
    
    
      <a href="optimizer/pushdown.html" class="md-nav__link">Pushdown</a>
      
    
    </li></ul>
    
    </li>
    <li class="md-nav__item">
    
    
      <a href="connector.html" class="md-nav__link">Connectors</a>
      
    
    </li>
    <li class="md-nav__item">
    
    
      <a href="functions.html" class="md-nav__link">Functions and Operators</a>
      
    
    </li>
    <li class="md-nav__item">
    
    
      <a href="language.html" class="md-nav__link">SQL Language</a>
      
    
    </li>
    <li class="md-nav__item">
    
    
      <a href="sql.html" class="md-nav__link">SQL Statement Syntax</a>
      
    
    </li>
    <li class="md-nav__item">
    
    
      <a href="migration.html" class="md-nav__link">Migration</a>
      
    
    </li>
    <li class="md-nav__item">
    
    
      <a href="develop.html" class="md-nav__link">Developer Guide</a>
      
    
    </li>
    <li class="md-nav__item">
    
    
      <a href="release.html" class="md-nav__link">Release Notes</a>
      
    
    </li>
  </ul>
  

</nav>
              </div>
            </div>
          </div>
          <div class="md-sidebar md-sidebar--secondary" data-md-component="toc">
            <div class="md-sidebar__scrollwrap">
              <div class="md-sidebar__inner">
                
<nav class="md-nav md-nav--secondary">
    <ul class="md-nav__list" data-md-scrollfix="">
    </ul>
</nav>
              </div>
            </div>
          </div>
        
        <div class="md-content">
          <article class="md-content__inner md-typeset" role="main">
            
  
<h1 id="optimizer--page-root">Query Optimizer<a class="headerlink" href="#optimizer--page-root" title="Permalink to this headline">#</a></h1>
<div class="toctree-wrapper compound">
<ul>
<li class="toctree-l1"><a class="reference internal" href="optimizer/statistics.html">Table Statistics</a></li>
<li class="toctree-l1"><a class="reference internal" href="optimizer/cost-in-explain.html">Cost in EXPLAIN</a></li>
<li class="toctree-l1"><a class="reference internal" href="optimizer/cost-based-optimizations.html">Cost based optimizations</a></li>
<li class="toctree-l1"><a class="reference internal" href="optimizer/pushdown.html">Pushdown</a></li>
</ul>
</div>


          </article>
        </div>
      </div>
    </main>
  </div>
  <footer class="md-footer">
    <div class="md-footer-nav">
      <nav class="md-footer-nav__inner md-grid">
          
            <a href="admin/dist-sort.html" title="Distributed Sort"
               class="md-flex md-footer-nav__link md-footer-nav__link--prev"
               rel="prev">
              <div class="md-flex__cell md-flex__cell--shrink">
                <i class="md-icon md-icon--arrow-back md-footer-nav__button"></i>
              </div>
              <div class="md-flex__cell md-flex__cell--stretch md-footer-nav__title">
                <span class="md-flex__ellipsis">
                  <span
                      class="md-footer-nav__direction"> Previous </span> Distributed Sort </span>
              </div>
            </a>
          
          
            <a href="optimizer/statistics.html" title="Table Statistics"
               class="md-flex md-footer-nav__link md-footer-nav__link--next"
               rel="next">
            <div class="md-flex__cell md-flex__cell--stretch md-footer-nav__title"><span
                class="md-flex__ellipsis"> <span
                class="md-footer-nav__direction"> Next </span> Table Statistics </span>
            </div>
            <div class="md-flex__cell md-flex__cell--shrink"><i
                class="md-icon md-icon--arrow-forward md-footer-nav__button"></i>
            </div>
          
        </a>
        
      </nav>
    </div>
    <div class="md-footer-meta md-typeset">
      <div class="md-footer-meta__inner md-grid">
        <div class="md-footer-copyright">
        </div>
      </div>
    </div>
  </footer>
  <script src="_static/javascripts/application.js"></script>
  <script>app.initialize({version: "1.0.4", url: {base: ".."}})</script>
  </body>
</html>