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  • Committer: Package Import Robot
  • Author(s): Piotr Ożarowski
  • Date: 2014-06-27 20:17:13 UTC
  • mfrom: (1.4.28)
  • Revision ID: package-import@ubuntu.com-20140627201713-g6p1kq8q1qenztrv
Tags: 0.9.6-1
http://bugs.debian.org/747852
http://bugs.debian.org/752145
* New upstream release
* Remove Python 3.X build tag files, thanks to Matthias Urlichs for the
  patch (closes: #747852)
* python-fdb isn't in the Debian archive yet so default dialect for firebird://
  URLs is changed to obsolete kinterbasdb, thanks to Russell Stuart for the
  patch (closes: #752145)

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doc/core/pooling.html
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    <script type="text/javascript">
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      var DOCUMENTATION_OPTIONS = {
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          URL_ROOT:    '../',
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          VERSION:     '0.9.4',
 
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          VERSION:     '0.9.6',
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          COLLAPSE_MODINDEX: false,
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          FILE_SUFFIX: '.html'
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      };
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        <script type="text/javascript" src="../_static/doctools.js"></script>
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    <!-- end iterate through sphinx environment script_files -->
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    <script type="text/javascript" src="../_static/detectmobile.js"></script>
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    <script type="text/javascript" src="../_static/init.js"></script>
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    <link rel="index" title="Index" href="../genindex.html" />
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    <link rel="search" title="Search" href="../search.html" />
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<div id="docs-container">
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<div id="docs-top-navigation-container" class="body-background">
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<div id="docs-header">
 
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    <div id="docs-version-header">
 
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        Release: <span class="version-num">0.9.6</span> | Release Date: June 23, 2014
 
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    </div>
 
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    <h1>SQLAlchemy 0.9 Documentation</h1>
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    <div id="docs-search">
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    Search:
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    <form class="search" action="../search.html" method="get">
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      <input type="text" name="q" size="18" /> <input type="submit" value="Search" />
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      <input type="hidden" name="check_keywords" value="yes" />
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      <input type="hidden" name="area" value="default" />
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    </form>
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    </div>
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    <div id="docs-version-header">
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        Release: <span class="version-num">0.9.4</span> | Release Date: March 28, 2014
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    </div>
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</div>
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<div id="docs-top-navigation">
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    <div id="docs-top-page-control" class="docs-navigation-links">
 
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</div>
 
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</div>
 
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<div id="docs-body-container">
 
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    <div id="fixed-sidebar" class="withsidebar">
 
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        <div id="docs-sidebar-popout">
 
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            <h3><a href="../index.html">SQLAlchemy 0.9 Documentation</a></h3>
 
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            <p id="sidebar-paginate">
 
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                    <a href="index.html" title="SQLAlchemy Core">Up</a> |
 
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                    <a href="connections.html" title="Working with Engines and Connections">Prev</a> |
 
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                    <a href="event.html" title="Events">Next</a>
 
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            </p>
 
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            <p id="sidebar-topnav">
 
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                <a href="../index.html">Contents</a> |
 
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                <a href="../genindex.html">Index</a>
 
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            </p>
 
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            <div id="sidebar-search">
 
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                <form class="search" action="../search.html" method="get">
 
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                  <input type="text" name="q" size="12" /> <input type="submit" value="Search" />
 
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                  <input type="hidden" name="check_keywords" value="yes" />
 
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                  <input type="hidden" name="area" value="default" />
 
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                </form>
 
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            </div>
 
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        </div>
 
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        <div id="docs-sidebar">
 
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        <h3><a href="#">            
 
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                Connection Pooling
 
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        </a></h3>
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        <ul>
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            <li>Prev:
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            <a href="connections.html" title="previous chapter">Working with Engines and Connections</a>
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            </li>
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            <li>Next:
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            <a href="event.html" title="next chapter">Events</a>
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            </li>
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        <li>
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            <a href="../contents.html">Table of Contents</a> |
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            <a href="../genindex.html">Index</a>
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            | <a href="../_sources/core/pooling.txt">view source
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        </li>
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        </ul>
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    </div>
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    <div id="docs-navigation-banner">
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        <a href="../index.html">SQLAlchemy 0.9 Documentation</a>
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                » <a href="index.html" title="SQLAlchemy Core">SQLAlchemy Core</a>
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        » 
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                Connection Pooling
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        <h2>
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                Connection Pooling
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        </h2>
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    </div>
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</div>
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<div id="docs-body-container">
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    <div id="docs-sidebar">
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    <h3><a href="../index.html">Table of Contents</a></h3>
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    <ul>
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<li><a class="reference internal" href="#">Connection Pooling</a><ul>
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<li><a class="reference internal" href="#connection-pool-configuration">Connection Pool Configuration</a></li>
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<li><a class="reference internal" href="#switching-pool-implementations">Switching Pool Implementations</a></li>
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</ul>
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    <h4>Previous Topic</h4>
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    <p>
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    <a href="connections.html" title="previous chapter">Working with Engines and Connections</a>
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    </p>
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    <h4>Next Topic</h4>
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    <p>
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    <a href="event.html" title="next chapter">Events</a>
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    </p>
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    <h4>Quick Search</h4>
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    <p>
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    <form class="search" action="../search.html" method="get">
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      <input type="text" name="q" size="18" /> <input type="submit" value="Search" />
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      <input type="hidden" name="check_keywords" value="yes" />
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      <input type="hidden" name="area" value="default" />
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    </form>
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    </p>
 
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        </div>
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    </div>
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    <div id="docs-body" class="withsidebar" >
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<div class="section" id="module-sqlalchemy.pool">
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<span class="n">cursor</span><span class="o">.</span><span class="n">execute</span><span class="p">(</span><span class="s">&quot;select foo&quot;</span><span class="p">)</span></pre></div>
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</div>
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<p>The purpose of the transparent proxy is to intercept the <tt class="docutils literal"><span class="pre">close()</span></tt> call,
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such that instead of the DBAPI connection being closed, it&#8217;s returned to the
 
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such that instead of the DBAPI connection being closed, it is returned to the
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pool:</p>
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<div class="highlight-python"><div class="highlight"><pre><span class="c"># &quot;close&quot; the connection.  Returns</span>
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<span class="c"># it to the pool.</span>
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<h3>Disconnect Handling - Pessimistic<a class="headerlink" href="#disconnect-handling-pessimistic" title="Permalink to this headline">¶</a></h3>
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<p>At the expense of some extra SQL emitted for each connection checked out from the pool,
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a &#8220;ping&#8221; operation established by a checkout event handler
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can detect an invalid connection before it&#8217;s used:</p>
 
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can detect an invalid connection before it is used:</p>
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<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">exc</span>
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<span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">event</span>
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<span class="kn">from</span> <span class="nn">sqlalchemy.pool</span> <span class="kn">import</span> <span class="n">Pool</span>