mirror of
https://github.com/berkeleydb/libdb.git
synced 2024-11-16 17:16:25 +00:00
368 lines
16 KiB
HTML
368 lines
16 KiB
HTML
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
|
||
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
|
||
<html xmlns="http://www.w3.org/1999/xhtml">
|
||
<head>
|
||
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
|
||
<title>DB->verify()</title>
|
||
<link rel="stylesheet" href="apiReference.css" type="text/css" />
|
||
<meta name="generator" content="DocBook XSL Stylesheets V1.73.2" />
|
||
<link rel="start" href="index.html" title="Berkeley DB C API Reference" />
|
||
<link rel="up" href="db.html" title="Chapter 2. The DB Handle" />
|
||
<link rel="prev" href="dbupgrade.html" title="DB->upgrade()" />
|
||
<link rel="next" href="db_heap_rid.html" title="DB_HEAP_RID" />
|
||
</head>
|
||
<body>
|
||
<div xmlns="" class="navheader">
|
||
<div class="libver">
|
||
<p>Library Version 11.2.5.3</p>
|
||
</div>
|
||
<table width="100%" summary="Navigation header">
|
||
<tr>
|
||
<th colspan="3" align="center">DB->verify()</th>
|
||
</tr>
|
||
<tr>
|
||
<td width="20%" align="left"><a accesskey="p" href="dbupgrade.html">Prev</a> </td>
|
||
<th width="60%" align="center">Chapter 2.
|
||
The DB Handle
|
||
</th>
|
||
<td width="20%" align="right"> <a accesskey="n" href="db_heap_rid.html">Next</a></td>
|
||
</tr>
|
||
</table>
|
||
<hr />
|
||
</div>
|
||
<div class="sect1" lang="en" xml:lang="en">
|
||
<div class="titlepage">
|
||
<div>
|
||
<div>
|
||
<h2 class="title" style="clear: both"><a id="dbverify"></a>DB->verify()</h2>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<pre class="programlisting">#include <db.h>
|
||
|
||
int
|
||
DB->verify(DB *db, const char *file,
|
||
const char *database, FILE *outfile, u_int32_t flags); </pre>
|
||
<p>
|
||
The <code class="methodname">DB->verify()</code> method verifies the integrity of all databases in
|
||
the file specified by the <span class="bold"><strong>file</strong></span>
|
||
parameter, and optionally outputs the databases' key/data pairs to the
|
||
file stream specified by the <span class="bold"><strong>outfile</strong></span>
|
||
parameter.
|
||
</p>
|
||
<p>
|
||
<span class="bold"><strong>The <code class="methodname">DB->verify()</code> method does not perform any
|
||
locking, even in Berkeley DB environments that are configured with a
|
||
locking subsystem. As such, it should only be used on files that are
|
||
not being modified by another thread of control.</strong></span>
|
||
</p>
|
||
<p>
|
||
The <code class="methodname">DB->verify()</code> method may not be called after the
|
||
<a class="xref" href="dbopen.html" title="DB->open()">DB->open()</a> method is called.
|
||
</p>
|
||
<p>
|
||
The <a class="link" href="db.html" title="Chapter 2. The DB Handle">DB</a> handle may not be
|
||
accessed again after <code class="methodname">DB->verify()</code> is called, regardless of its
|
||
return.
|
||
</p>
|
||
<p>
|
||
The <code class="methodname">DB->verify()</code> method is the
|
||
underlying method used by the
|
||
<a class="link" href="db_verify.html" title="db_verify">db_verify</a> utility. See the
|
||
<a class="link" href="db_verify.html" title="db_verify">db_verify</a> utility source code for
|
||
an example of using <code class="methodname">DB->verify()</code> in a
|
||
IEEE/ANSI Std 1003.1 (POSIX) environment.
|
||
</p>
|
||
<p>
|
||
The <code class="methodname">DB->verify()</code> method will return DB_VERIFY_BAD if a database is
|
||
corrupted. When the DB_SALVAGE flag is specified, the DB_VERIFY_BAD
|
||
return means that all key/data pairs in the file may not have been
|
||
successfully output. Unless otherwise specified, the <code class="methodname">DB->verify()</code>
|
||
<span>
|
||
<span>
|
||
method returns a non-zero error value on failure and 0 on success.
|
||
</span>
|
||
|
||
</span>
|
||
</p>
|
||
<div class="sect2" lang="en" xml:lang="en">
|
||
<div class="titlepage">
|
||
<div>
|
||
<div>
|
||
<h3 class="title"><a id="idp58731056"></a>Parameters</h3>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<div class="sect3" lang="en" xml:lang="en">
|
||
<div class="titlepage">
|
||
<div>
|
||
<div>
|
||
<h4 class="title"><a id="idp58738904"></a>file</h4>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<p>
|
||
The <span class="bold"><strong>file</strong></span> parameter is the physical
|
||
file in which the databases to be verified are found.
|
||
</p>
|
||
</div>
|
||
<div class="sect3" lang="en" xml:lang="en">
|
||
<div class="titlepage">
|
||
<div>
|
||
<div>
|
||
<h4 class="title"><a id="idp58651416"></a>database</h4>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<p>
|
||
The <span class="bold"><strong>database</strong></span> parameter is the
|
||
database in <span class="bold"><strong>file</strong></span> on which the
|
||
database checks for btree and duplicate sort order and for hashing are
|
||
to be performed. See the DB_ORDERCHKONLY flag for more information.
|
||
</p>
|
||
<p>
|
||
The database parameter must be set to NULL except when the
|
||
DB_ORDERCHKONLY flag is set.
|
||
</p>
|
||
</div>
|
||
<div class="sect3" lang="en" xml:lang="en">
|
||
<div class="titlepage">
|
||
<div>
|
||
<div>
|
||
<h4 class="title"><a id="idp58680440"></a>outfile</h4>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<p>
|
||
The <span class="bold"><strong>outfile</strong></span> parameter is an optional
|
||
file stream to which the databases' key/data pairs are written.
|
||
</p>
|
||
</div>
|
||
<div class="sect3" lang="en" xml:lang="en">
|
||
<div class="titlepage">
|
||
<div>
|
||
<div>
|
||
<h4 class="title"><a id="idp58727008"></a>flags</h4>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<p>
|
||
The <span class="bold"><strong>flags</strong></span> parameter must be set to 0
|
||
or the following value:
|
||
</p>
|
||
<div class="itemizedlist">
|
||
<ul type="disc">
|
||
<li>
|
||
<p><a id="verify_DB_SALVAGE"></a>
|
||
<code class="literal">DB_SALVAGE</code>
|
||
</p>
|
||
<p>
|
||
Write the key/data pairs from all databases in the file to the file
|
||
stream named in the <span class="bold"><strong>outfile</strong></span>
|
||
parameter. Key values are written for Btree, Hash and Queue
|
||
databases, but not for Recno databases.
|
||
</p>
|
||
<p>
|
||
The output format is the same as that specified for the <a class="link" href="db_dump.html" title="db_dump">db_dump</a> utility, and can be used
|
||
as input for the <a class="link" href="db_load.html" title="db_load">db_load</a>
|
||
utility.
|
||
</p>
|
||
<p>
|
||
Because the key/data pairs are output in page order as opposed to the
|
||
sort order used by <a class="link" href="db_dump.html" title="db_dump">db_dump</a>, using <code class="methodname">DB->verify()</code> to
|
||
dump key/data pairs normally produces less than optimal loads for
|
||
Btree databases.
|
||
</p>
|
||
</li>
|
||
</ul>
|
||
</div>
|
||
<p>
|
||
In addition, the following flags may be set by bitwise inclusively
|
||
<span class="bold"><strong>OR</strong></span>'ing them into the <span class="bold"><strong>flags</strong></span> parameter:
|
||
</p>
|
||
<div class="itemizedlist">
|
||
<ul type="disc">
|
||
<li>
|
||
<p><a id="verify_DB_AGGRESSIVE"></a>
|
||
<code class="literal">DB_AGGRESSIVE</code>
|
||
</p>
|
||
<p>
|
||
Output <span class="bold"><strong>all</strong></span> the key/data pairs in the
|
||
file that can be found. By default, <code class="methodname">DB->verify()</code> does not assume
|
||
corruption. For example, if a key/data pair on a page is marked as
|
||
deleted, it is not then written to the output file. When
|
||
DB_AGGRESSIVE is specified, corruption is assumed, and any key/data
|
||
pair that can be found is written. In this case, key/data pairs that
|
||
are corrupted or have been deleted may appear in the output (even if
|
||
the file being salvaged is in no way corrupt), and the output will
|
||
almost certainly require editing before being loaded into a database.
|
||
</p>
|
||
</li>
|
||
<li>
|
||
<p><a id="verify_DB_PRINTABLE"></a>
|
||
<code class="literal">DB_PRINTABLE</code>
|
||
</p>
|
||
<p>
|
||
When using the DB_SALVAGE flag, if characters in either the key or
|
||
data items are printing characters (as defined by <span class="bold"><strong>isprint</strong></span>(3)), use printing characters to
|
||
represent them. This flag permits users to use standard text editors
|
||
and tools to modify the contents of databases or selectively remove
|
||
data from salvager output.
|
||
</p>
|
||
<p>
|
||
Note: different systems may have different notions about what
|
||
characters are considered <span class="emphasis"><em>printing characters</em></span>,
|
||
and databases dumped in this manner may be less portable to external
|
||
systems.
|
||
</p>
|
||
</li>
|
||
<li>
|
||
<p><a id="verify_DB_NOORDERCHK"></a>
|
||
<code class="literal">DB_NOORDERCHK</code>
|
||
</p>
|
||
<p>
|
||
Skip the database checks for btree and duplicate sort order and for
|
||
hashing.
|
||
</p>
|
||
<p>
|
||
The <code class="methodname">DB->verify()</code> method normally verifies that btree keys and
|
||
duplicate items are correctly sorted, and hash keys are correctly
|
||
hashed. If the file being verified contains multiple databases using
|
||
differing sorting or hashing algorithms, some of them must necessarily
|
||
fail database verification because only one sort order or hash
|
||
function can be specified before <code class="methodname">DB->verify()</code> is called. To verify
|
||
files with multiple databases having differing sorting orders or
|
||
hashing functions, first perform verification of the file as a whole
|
||
by using the DB_NOORDERCHK flag, and then individually verify the sort
|
||
order and hashing function for each database in the file using the
|
||
DB_ORDERCHKONLY flag.
|
||
</p>
|
||
</li>
|
||
<li>
|
||
<p><a id="verify_DB_ORDERCHKONLY"></a>
|
||
<code class="literal">DB_ORDERCHKONLY</code>
|
||
</p>
|
||
<p>
|
||
Perform the database checks for btree and duplicate sort order and for
|
||
hashing, skipped by DB_NOORDERCHK.
|
||
</p>
|
||
<p>
|
||
When this flag is specified, a <span class="bold"><strong>database</strong></span> parameter should also be specified,
|
||
indicating the database in the physical file which is to be checked.
|
||
This flag is only safe to use on databases that have already
|
||
successfully been verified using <code class="methodname">DB->verify()</code> with the DB_NOORDERCHK
|
||
flag set.
|
||
</p>
|
||
</li>
|
||
</ul>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<div class="sect2" lang="en" xml:lang="en">
|
||
<div class="titlepage">
|
||
<div>
|
||
<div>
|
||
<h3 class="title"><a id="idp58764232"></a>Environment Variables</h3>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<p>
|
||
If the database was opened within a database environment, the
|
||
environment variable <code class="literal">DB_HOME</code> may be used as the path of the
|
||
database environment home.
|
||
</p>
|
||
<p>
|
||
<code class="methodname">DB->verify()</code> is affected by any database directory specified using the
|
||
<a class="xref" href="envset_data_dir.html" title="DB_ENV->set_data_dir()">DB_ENV->set_data_dir()</a>
|
||
method, or by setting the "set_data_dir" string
|
||
in the environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file.
|
||
</p>
|
||
</div>
|
||
<div class="sect2" lang="en" xml:lang="en">
|
||
<div class="titlepage">
|
||
<div>
|
||
<div>
|
||
<h3 class="title"><a id="idp58765312"></a>Errors</h3>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<p>
|
||
The <code class="methodname">DB->verify()</code> <span>
|
||
<span>
|
||
method may fail and return one of the following non-zero errors:
|
||
</span>
|
||
|
||
</span>
|
||
</p>
|
||
<div class="sect3" lang="en" xml:lang="en">
|
||
<div class="titlepage">
|
||
<div>
|
||
<div>
|
||
<h4 class="title"><a id="idp58770016"></a>EINVAL</h4>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<p>
|
||
If the method was called after <a class="xref" href="dbopen.html" title="DB->open()">DB->open()</a>
|
||
was called; or if an invalid flag value or parameter was specified.
|
||
</p>
|
||
</div>
|
||
<div class="sect3" lang="en" xml:lang="en">
|
||
<div class="titlepage">
|
||
<div>
|
||
<div>
|
||
<h4 class="title"><a id="idp58759880"></a>ENOENT</h4>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<p>
|
||
The file or directory does not exist.
|
||
</p>
|
||
</div>
|
||
</div>
|
||
<div class="sect2" lang="en" xml:lang="en">
|
||
<div class="titlepage">
|
||
<div>
|
||
<div>
|
||
<h3 class="title"><a id="idp58754384"></a>Class</h3>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<p>
|
||
<a class="link" href="db.html" title="Chapter 2. The DB Handle">DB</a>
|
||
</p>
|
||
</div>
|
||
<div class="sect2" lang="en" xml:lang="en">
|
||
<div class="titlepage">
|
||
<div>
|
||
<div>
|
||
<h3 class="title"><a id="idp58754120"></a>See Also</h3>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<p>
|
||
<a class="xref" href="db.html#dblist" title="Database and Related Methods">Database and Related Methods</a>
|
||
</p>
|
||
</div>
|
||
</div>
|
||
<div class="navfooter">
|
||
<hr />
|
||
<table width="100%" summary="Navigation footer">
|
||
<tr>
|
||
<td width="40%" align="left"><a accesskey="p" href="dbupgrade.html">Prev</a> </td>
|
||
<td width="20%" align="center">
|
||
<a accesskey="u" href="db.html">Up</a>
|
||
</td>
|
||
<td width="40%" align="right"> <a accesskey="n" href="db_heap_rid.html">Next</a></td>
|
||
</tr>
|
||
<tr>
|
||
<td width="40%" align="left" valign="top">DB->upgrade() </td>
|
||
<td width="20%" align="center">
|
||
<a accesskey="h" href="index.html">Home</a>
|
||
</td>
|
||
<td width="40%" align="right" valign="top"> DB_HEAP_RID</td>
|
||
</tr>
|
||
</table>
|
||
</div>
|
||
</body>
|
||
</html>
|