1<?xml version="1.0" encoding="UTF-8" standalone="no"?> 2<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 3<html xmlns="http://www.w3.org/1999/xhtml"> 4 <head> 5 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> 6 <title>txn commit</title> 7 <link rel="stylesheet" href="apiReference.css" type="text/css" /> 8 <meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /> 9 <link rel="start" href="index.html" title="Berkeley DB TCL API Reference" /> 10 <link rel="up" href="tclapi.html" title="Chapter��1.�� Berkeley DB Tcl APIs" /> 11 <link rel="prev" href="txn_checkpoint.html" title="env txn_checkpoint" /> 12 <link rel="next" href="version.html" title="berkdb version" /> 13 </head> 14 <body> 15 <div class="navheader"> 16 <table width="100%" summary="Navigation header"> 17 <tr> 18 <th colspan="3" align="center"><span class="emphasis"><em>txn</em></span> commit</th> 19 </tr> 20 <tr> 21 <td width="20%" align="left"><a accesskey="p" href="txn_checkpoint.html">Prev</a>��</td> 22 <th width="60%" align="center">Chapter��1.�� 23 Berkeley DB Tcl APIs 24 </th> 25 <td width="20%" align="right">��<a accesskey="n" href="version.html">Next</a></td> 26 </tr> 27 </table> 28 <hr /> 29 </div> 30 <div class="sect1" lang="en" xml:lang="en"> 31 <div class="titlepage"> 32 <div> 33 <div> 34 <h2 class="title" style="clear: both"><a id="txn_commit"></a><span class="emphasis"><em>txn</em></span> commit</h2> 35 </div> 36 </div> 37 </div> 38 <pre class="programlisting">txn commit 39 [-nosync] 40 [-sync] </pre> 41 <p> 42 The <span class="emphasis"><em>txn</em></span> <span class="bold"><strong>commit</strong></span> 43 command ends the transaction. 44 </p> 45 <p> 46 In the case of nested transactions, if the transaction is a parent 47 transaction with unresolved (neither committed or aborted) child 48 transactions, the child transactions are aborted and the commit of the 49 parent will succeed. 50 </p> 51 <p> 52 In the case of nested transactions, if the transaction is a child 53 transaction, its locks are not released, but are acquired by its 54 parent. Although the commit of the child transaction will succeed, the 55 actual resolution of the child transaction is postponed until the 56 parent transaction is committed or aborted; that is, if its parent 57 transaction commits, it will be committed, and if its parent 58 transaction aborts, it will be aborted. 59 </p> 60 <p> 61 If the <span class="bold"><strong>-nosync</strong></span> option is not 62 specified, a commit log record is written and flushed to disk, as are 63 all previously written log records. 64 </p> 65 <p> 66 The options are as follows: 67 </p> 68 <div class="itemizedlist"> 69 <ul type="disc"> 70 <li> 71 <p> 72 <span class="bold"><strong>-nosync</strong></span> 73 </p> 74 <p> 75 Do not synchronously flush the log. This means the transaction will 76 exhibit the ACI (atomicity, consistency, and isolation) properties, 77 but not D (durability); that is, database integrity will be 78 maintained, but it is possible that this transaction may be undone 79 during recovery instead of being redone. 80 </p> 81 <p> 82 This behavior may be set for an entire Berkeley DB environment as part 83 of the <span class="bold"><strong>berkdb env</strong></span> call. 84 </p> 85 </li> 86 <li> 87 <p> 88 <span class="bold"><strong>-sync</strong></span> 89 </p> 90 <p> 91 Synchronously flush the log. This means the transaction will exhibit 92 all of the ACID (atomicity, consistency, isolation and durability) 93 properties. 94 </p> 95 <p> 96 This behavior is the default for Berkeley DB environments unless the 97 <span class="bold"><strong>-nosync</strong></span> option was specified to the 98 <span class="bold"><strong>berkdb env</strong></span> or 99 <span class="emphasis"><em>env</em></span> <span class="bold"><strong>txn</strong></span> calls. 100 </p> 101 </li> 102 </ul> 103 </div> 104 <p> 105 After <span class="emphasis"><em>txn</em></span> <span class="bold"><strong>commit</strong></span> 106 has been called, regardless of its return, the <span class="bold"><strong>txn</strong></span> handle may not be accessed again. If 107 <span class="emphasis"><em>txn</em></span> <span class="bold"><strong>commit</strong></span> 108 encounters an error, this transaction and all child transactions of 109 this transaction are aborted. 110 </p> 111 <p> 112 The <span class="emphasis"><em>txn</em></span> <span class="bold"><strong>commit</strong></span> 113 command returns 0 on success, and in the case of error, a Tcl error is 114 thrown. 115 </p> 116 </div> 117 <div class="navfooter"> 118 <hr /> 119 <table width="100%" summary="Navigation footer"> 120 <tr> 121 <td width="40%" align="left"><a accesskey="p" href="txn_checkpoint.html">Prev</a>��</td> 122 <td width="20%" align="center"> 123 <a accesskey="u" href="tclapi.html">Up</a> 124 </td> 125 <td width="40%" align="right">��<a accesskey="n" href="version.html">Next</a></td> 126 </tr> 127 <tr> 128 <td width="40%" align="left" valign="top"><span class="emphasis"><em>env</em></span> txn_checkpoint��</td> 129 <td width="20%" align="center"> 130 <a accesskey="h" href="index.html">Home</a> 131 </td> 132 <td width="40%" align="right" valign="top">��berkdb version</td> 133 </tr> 134 </table> 135 </div> 136 </body> 137</html> 138