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90 lines
3.8 KiB
HTML
90 lines
3.8 KiB
HTML
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<?xml version="1.0" encoding="UTF-8" standalone="no"?>
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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<html xmlns="http://www.w3.org/1999/xhtml">
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
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<title>Multiprocess Applications</title>
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<link rel="stylesheet" href="gettingStarted.css" type="text/css" />
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<meta name="generator" content="DocBook XSL Stylesheets V1.73.2" />
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<link rel="start" href="index.html" title="Getting Started with Berkeley DB Java Edition" />
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<link rel="up" href="concurrentProcessing.html" title="Appendix A. Concurrent Processing in Berkeley DB Java Edition" />
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<link rel="prev" href="concurrentProcessing.html" title="Appendix A. Concurrent Processing in Berkeley DB Java Edition" />
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</head>
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<body>
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<div xmlns="" class="navheader">
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<div class="libver">
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<p>Library Version 12.2.7.5</p>
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</div>
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<table width="100%" summary="Navigation header">
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<tr>
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<th colspan="3" align="center">Multiprocess Applications</th>
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</tr>
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<tr>
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<td width="20%" align="left"><a accesskey="p" href="concurrentProcessing.html">Prev</a> </td>
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<th width="60%" align="center">Appendix A. Concurrent Processing in Berkeley DB Java Edition</th>
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<td width="20%" align="right"> </td>
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</tr>
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</table>
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<hr />
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</div>
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<div class="sect1" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h2 class="title" style="clear: both"><a id="multiprocess"></a>Multiprocess Applications</h2>
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</div>
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</div>
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</div>
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<p>
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Note the following if you are writing an application that wants to access JE databases from multiple
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processes:
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</p>
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<div class="itemizedlist">
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<ul type="disc">
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<li>
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<p>
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In JE, you must use environments. Further, a database can be opened for write access only if the
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environment is opened for write access. Finally, only one process may have an environment opened for
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write access at a time.
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</p>
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</li>
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<li>
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<p>
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If your process attempts to open an environment for write, and another process has already opened that
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environment for write, then the open will fail. In this event, the process must either exit or open the
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environment as read-only.
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</p>
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</li>
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<li>
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<p>
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A process that opens an environment for read-only receives a snapshot of the data in that environment.
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If another process modifies the environment's databases in any way, the read-only version of the data
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will not be updated until the read-only process closes and reopens the environment (and by extension all
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databases in that environment).
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</p>
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</li>
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</ul>
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</div>
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</div>
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<div class="navfooter">
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<hr />
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<table width="100%" summary="Navigation footer">
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<tr>
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<td width="40%" align="left"><a accesskey="p" href="concurrentProcessing.html">Prev</a> </td>
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<td width="20%" align="center">
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<a accesskey="u" href="concurrentProcessing.html">Up</a>
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</td>
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<td width="40%" align="right"> </td>
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</tr>
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<tr>
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<td width="40%" align="left" valign="top">Appendix A. Concurrent Processing in Berkeley DB Java Edition </td>
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<td width="20%" align="center">
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<a accesskey="h" href="index.html">Home</a>
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</td>
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<td width="40%" align="right" valign="top"> </td>
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</tr>
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</table>
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</div>
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</body>
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</html>
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