pg_repack/doc/pg_reorg.html

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<h1><a name="pg_reorg"></a>pg_reorg</h1>

<div><a name="name"></a>
<h2>Name</h2>
pg_reorg -- Reorganize tables in PostgreSQL databases without any locks.
</div>

<div><a name="synopsis"></a>
<h2>Synopsis</h2>
<p>
<tt>pg_reorg</tt> [<tt><i>connection-options</i></tt>...]  [<tt><i>message-options</i></tt>...]  [<tt><i>order-options</i></tt>...]  [<tt><i>target-options</i></tt>...]
</p>
<p>There 4 option categories.
See also <a href="#options">options</a> for details.</p>
<dl>
 <dt><tt>connection-options</tt></dt>
  <dd><tt>-h</tt> [<tt>--host</tt>] <tt><i>host</i></tt></dd>
  <dd><tt>-p</tt> [<tt>--port</tt>] <tt><i>port</i></tt></dd>
  <dd><tt>-U</tt> [<tt>--username</tt>] <tt><i>username</i></tt></dd>
  <dd><tt>-W</tt> [<tt>--password</tt>]</dd>
 <dt><tt>message-options</tt></dt>
  <dd><tt>-e</tt> [<tt>--echo</tt>]</dd>
  <dd><tt>-q</tt> [<tt>--quiet</tt>]</dd>
  <dd><tt>-v</tt> [<tt>--verbose</tt>]</dd>
 <dt><tt>order-options</tt></dt>
  <dd><tt>-o</tt> [<tt>--order-by</tt>]  <tt><i>columns [,...]</i></tt></dd>
  <dd><tt>-n</tt> [<tt>--no-order</tt>]</dd>
 <dt><tt>target-options</tt></dt>
  <dd><tt>-a</tt> [<tt>--all</tt>]</dd>
  <dd><tt>-d</tt> [<tt>--dbname</tt>] <tt><i>dbname</i></tt></dd>
  <dd><tt>-t</tt> [<tt>--table</tt>] <tt><i>table</i></tt></dd>
</dl>
</div>

<div>
<a name="description"></a>
<h2>Description</h2>
<p>pg_reorg is an utility program to reorganize tables in PostgreSQL databases.
Unlike <a href="http://www.postgresql.jp/document/current/html/app-clusterdb.html"><tt>clusterdb</tt></a>, it doesn't block any selections and updates during reorganization.
You can choose one of the following methods to reorganize.</p>
<ul>
<li>Online CLUSTER (ordered by cluster index)</li>
<li>Ordered by specified columns</li>
<li>Online VACUUM FULL (packing rows only)</li>
</ul>
<p>NOTICE:</p>
<ul>
<li>Only superusers can use the utility.</li>
<li>Target table must have PRIMARY KEY.</li>
<li>You'd better to do <tt><a href="http://www.postgresql.jp/document/current/html/sql-analyze.html">ANALYZE</a></tt> after pg_reorg is completed.</li>
</ul>
</div>

<div><a name="examples"></a>
<h2>Examples</h2>
<p>Execute the following command to do online CLUSTER to all tables in <tt>test</tt> database.</p>
<PRE><SAMP>$ </SAMP><KBD>pg_reorg test</KBD></PRE>
<p>Execute the following command to do online VACUUM FULL to <tt>foo</tt> table in <tt>test</tt> database.</p>
<PRE><SAMP>$ </SAMP><KBD>pg_reorg --no-order --table foo -d test</KBD></PRE><p>
</p></div>

<div><a name="options"></a>
<h2>Options</h2>
<p>pg_reorg has command line options in 4 categolies.</p>
<div>
<dl>

<h3>connection-options</h3>
<p>Parameters to connect PostgreSQL.</p>

<div>
<dl>
<dt><tt>-h <tt><i>host</i></tt><br />
<tt>--host <tt><i>host</i></tt></dt>
<dd>Specifies the host name of the machine on which the server is running. If the value begins with a slash, it is used as the directory for the Unix domain socket. </dd>

<dt><tt>-p <tt><i>port</i></tt><br />
<tt>--port <tt><i>port</i></tt></dt>
<dd>Specifies the TCP port or local Unix domain socket file extension on which the server is listening for connections.</dd>

<dt><tt>-U <tt><i>username</i></tt><br />
<tt>--username <tt><i>username</i></tt></dt>
<dd>User name to connect as. </dd>

<dt><tt>-W</tt><br /><tt>--password</tt></dt>
<dd>Force pg_reorg to prompt for a password before connecting to a database.</dd>
<dd>This option is never essential, since pg_reorg will automatically prompt for a password if the server demands password authentication. However, vacuumdb will waste a connection attempt finding out that the server wants a password. In some cases it is worth typing <tt>-W</tt> to avoid the extra connection attempt. </dd>
</dl>
</div>

<h3>message-options</h3>
<p>Specifies message output by pg_reorg.
<tt>--quiet</tt> is ignored if some of the other options are specified.</p>

<dl>
<dt><tt>-e</tt><br /><tt>--echo</tt></dt>
<dd>Echo the commands that pg_reorg generates and sends to the server.</dd>
<dt><tt>-q</tt><br /><tt>--quiet</tt></dt>
<dd>Do not display progress messages. </dd>
<dt><tt>-v</tt><br /><tt>--verbose</tt></dt>
<dd>Print detailed information during processing.</dd>
</dl>

<h3>order-options</h3>
<p>Options to order rows.
If not specified, pg_reorg do online CLUSTER using cluster indexes.
Only one option can be specified.
</p>

<dl>
<dt><tt>-n</tt><br /><tt>--no-order</tt></dt>
<dd>Do online VACUUM FULL.</dd>

<dt><tt>-o</tt> <tt><i>columns [,...]</i></tt><br />
<tt>--order-by</tt> <tt><i>columns [,...]</i></tt></dt>
<dd>Do online CLUSTER ordered by specified columns.</dd>
</dl>


<h3>target-options</h3>
<p>
Options to specify target tables or databases.
You cannot use <tt>--all</tt> and <tt>--dbname</tt> or <tt>--table</tt> together.
</p>

<dl>
<dt><tt>-a</tt><br /><tt>--all</tt></dt>
<dd>Reorganize all databases.</dd>

<dt>
<tt>-d <tt><i>dbname</i></tt><br />
<tt>--dbname <tt><i>dbname</i></tt>
</dt>
<dd>Specifies the name of the database to be reorganized. If this is not specified and <tt>-a</tt> (or <tt>--all</tt>) is not used, the database name is read from the environment variable <tt>PGDATABASE</tt>. If that is not set, the user name specified for the connection is used. </dd>

<dt>
<tt>-t</tt> <tt><i>table</i></tt><br />
<tt>--table</tt> <tt><i>table</i></tt>
</dt>
<dd>Reorganize <tt><i>table</i></tt> only. If you don't specify this option, all tables in specified databases are reorganized.</dd>
</dl>
</div>

<div><a name="environment"></a>
	<h2>Environment</h2>	<div>
		<dl>
			<dt>
				<tt>PGDATABASE</tt><br />
				<tt>PGHOST</tt><br />
				<tt>PGPORT</tt><br />
				<tt>PGUSER</tt>
			</dt>
			<dd>Default connection parameters</dd>
		</dl>
	</div>
	<p>This utility, like most other PostgreSQL utilities, also uses the environment variables supported by libpq  (see <a href="http://developer.postgresql.org/pgdocs/postgres/libpq-envars.html">Environment Variables</a>).</p>
</div>

<div><a name="diagnostics"></a>
<h2>Diagnostics</h2>
<p>Error messages are reported when pg_reorg fails.
The following list shows the cause of errors.</p>
<p>You need to cleanup by hand after fatal erros.
To cleanup, execute $PGHOME/share/contrib/uninstall_pg_reorg.sql to the database where the error occured and then execute $PGHOME/share/contrib/pg_reorg.sql. (Do uninstall and reinstall.)</p>

<dl>
<dt>pg_reorg : reorg database "template1" ... skipped</dt>
<dd>pg_reorg is not installed in the database when <tt>--all</tt> option is specified.</dd>
<dd>Do register pg_reorg to the database.</dd>

<dt>ERROR: pg_reorg is not installed</dt>
<dd>pg_reorg is not installed in the database specified by <tt>--dbname</tt>.</dd>
<dd>Do register pg_reorg to the database.</dd>

<dt>ERROR: relation "table" has no primary key</dt>
<dd>The target table doesn't have PRIMARY KEY.</dd>
<dd>Define PRIMARY KEY to the table. (ALTER TABLE ADD PRIMARY KEY)</dd>

<dt>ERROR: relation "table" has no cluster key</dt>
<dd>The target table doesn't have CLUSTER KEY.</dd>
<dd>Define CLUSTER KEY to the table. (ALTER TABLE CLUSTER)</dd>

<dt>pg_reorg : query failed: ERROR:  column "col" does not exist</dt>
<dd>The target table doesn't have columns specified by <tt>--order-by</tt> option.</dd>
<dd>Specify existing columns.</dd>

<dt>ERROR: permission denied for schema reorg</dt>
<dd>Permission error.</dd>
<dd>pg_reorg must be executed by superusers.</dd>

<dt>pg_reorg : query failed: ERROR:  trigger "z_reorg_trigger" for relation "tbl" already exists</dt>
<dd>The target table already has a trigger named "z_reorg_trigger".</dd>
<dd>Delete or rename the trigger.</dd>

<dt>pg_reorg : trigger conflicted for tbl</dt>
<dd>The target table already has a trigger which follows by "z_reorg_trigger" in alphabetical order.</dd>
<dd>Delete or rename the trigger.</dd>
</dl>
</div>

<div><a name="restrictions"></a>
<h2>Restrictions</h2>
<p>pg_reorg has the following restrictions.
Be careful to avoid data corruptions.</p>

<h3>Temp tables</h3>
<p>pg_reorg cannot reorganize temp tables.</p>

<h3>GiST indexes</h3>
<p>pg_reorg cannot reorganize tables using GiST indexes.</p>

<h3>DDL commands</h3>
<p>You cannot do DDL commands <strong>except</strong> <tt>VACUUM</tt> and <tt>ANALYZE</tt> during pg_reorg.
In many case pg_reorg would fail and rollback collectly, but there are some cases ending with data-corruption .</p>

<dl>
<dt><tt>TRUNCATE</tt></dt>
<dd><tt>TRUNCATE</tt> is lost. Deleted rows still exist after pg_reorg.</dd>

<dt><tt>CREATE INDEX</tt></dt>
<dd>It causes index corruptions.</dd>

<dt><tt>ALTER TABLE ... ADD COLUMN</tt></dt>
<dd>It causes lost of data. Newly added columns are initialized with NULLs.</dd>

<dt><tt>ALTER TABLE ... ALTER COLUMN TYPE</tt></dt>
<dd>It causes data corruptions.</dd>

<dt><tt>ALTER TABLE ... SET TABLESPACE</tt></dt>
<dd>It causes data corruptions by wrong relfilenode.</dd>
</dl>
</div>

<div><a name="install"></a>
<h2>Installations</h2>
<p>pg_reorg can be installed like standard contrib modules.</p>
<h3>Build from source</h3>
<p>Place pg_reorg to $PGHOME/contrib/ and input make, make install.</p>
<h3>Register to database</h3>
<p>Start PostgreSQL and execute pg_reorg.sql in $PGHOME/share/contrib.</p>
</div>

<div><a name="requirement"></a>
<h2>Requirements</h2>
<dl>
<dt>PostgreSQL version</dt><dd>PostgreSQL 8.3</dd>
<dt>OS</dt><dd>RHEL 5.2, Windows XP SP3</dd>
<dt>Disks</dt><dd>Requires amount of disks twice larger than target table and indexes.</dd>
</dl>
</div>

<div><a name="seealso"></a>
<h2>See Also</h2>
<a href="http://developer.postgresql.org/pgdocs/postgres/app-clusterdb.html"><i><tt>clusterdb</tt></i></a>,
<a href="http://developer.postgresql.org/pgdocs/postgres/app-vacuumdb.html"><i><tt>vacuumdb</tt></i></a>
</div>

<hr>

<p align="right"><font size="2">
Copyright (c) 2008-2009, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
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Modify LOCK to LOCK-NOWAIT-and-loop at swap tables to avoid holding exclusive locks long time. Suggested by Kenny Gorman. 2009-04-16 06:01:01 +00:00			`<!DOCTYPE html PUBLIC "-//W3C//DTD html 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">`
			`<html>`
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			`<title>pg_reorg</title>`
			`<link rel="home" title="pg_reorg " href="index.html">`
			`<link rel="stylesheet" TYPE="text/css"href="style.css">`
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			`<body>`
			`<h1><a name="pg_reorg"></a>pg_reorg</h1>`

			`<div><a name="name"></a>`
			`<h2>Name</h2>`
			`pg_reorg -- Reorganize tables in PostgreSQL databases without any locks.`
			`</div>`

			`<div><a name="synopsis"></a>`
			`<h2>Synopsis</h2>`
			`<p>`
			`<tt>pg_reorg</tt> [<tt><i>connection-options</i></tt>...] [<tt><i>message-options</i></tt>...] [<tt><i>order-options</i></tt>...] [<tt><i>target-options</i></tt>...]`
			`</p>`
			`<p>There 4 option categories.`
			`See also <a href="#options">options</a> for details.</p>`
			`<dl>`
			`<dt><tt>connection-options</tt></dt>`
			`<dd><tt>-h</tt> [<tt>--host</tt>] <tt><i>host</i></tt></dd>`
			`<dd><tt>-p</tt> [<tt>--port</tt>] <tt><i>port</i></tt></dd>`
			`<dd><tt>-U</tt> [<tt>--username</tt>] <tt><i>username</i></tt></dd>`
			`<dd><tt>-W</tt> [<tt>--password</tt>]</dd>`
			`<dt><tt>message-options</tt></dt>`
			`<dd><tt>-e</tt> [<tt>--echo</tt>]</dd>`
			`<dd><tt>-q</tt> [<tt>--quiet</tt>]</dd>`
			`<dd><tt>-v</tt> [<tt>--verbose</tt>]</dd>`
			`<dt><tt>order-options</tt></dt>`
			`<dd><tt>-o</tt> [<tt>--order-by</tt>] <tt><i>columns [,...]</i></tt></dd>`
			`<dd><tt>-n</tt> [<tt>--no-order</tt>]</dd>`
			`<dt><tt>target-options</tt></dt>`
			`<dd><tt>-a</tt> [<tt>--all</tt>]</dd>`
			`<dd><tt>-d</tt> [<tt>--dbname</tt>] <tt><i>dbname</i></tt></dd>`
			`<dd><tt>-t</tt> [<tt>--table</tt>] <tt><i>table</i></tt></dd>`
			`</dl>`
			`</div>`

			`<div>`
			`<a name="description"></a>`
			`<h2>Description</h2>`
			`<p>pg_reorg is an utility program to reorganize tables in PostgreSQL databases.`
			`Unlike <a href="http://www.postgresql.jp/document/current/html/app-clusterdb.html"><tt>clusterdb</tt></a>, it doesn't block any selections and updates during reorganization.`
			`You can choose one of the following methods to reorganize.</p>`
			`<ul>`
			`<li>Online CLUSTER (ordered by cluster index)</li>`
			`<li>Ordered by specified columns</li>`
			`<li>Online VACUUM FULL (packing rows only)</li>`
			`</ul>`
			`<p>NOTICE:</p>`
			`<ul>`
			`<li>Only superusers can use the utility.</li>`
			`<li>Target table must have PRIMARY KEY.</li>`
			`<li>You'd better to do <tt><a href="http://www.postgresql.jp/document/current/html/sql-analyze.html">ANALYZE</a></tt> after pg_reorg is completed.</li>`
			`</ul>`
			`</div>`

			`<div><a name="examples"></a>`
			`<h2>Examples</h2>`
			`<p>Execute the following command to do online CLUSTER to all tables in <tt>test</tt> database.</p>`
			`<PRE><SAMP>$ </SAMP><KBD>pg_reorg test</KBD></PRE>`
			`<p>Execute the following command to do online VACUUM FULL to <tt>foo</tt> table in <tt>test</tt> database.</p>`
			`<PRE><SAMP>$ </SAMP><KBD>pg_reorg --no-order --table foo -d test</KBD></PRE><p>`
			`</p></div>`

			`<div><a name="options"></a>`
			`<h2>Options</h2>`
			`<p>pg_reorg has command line options in 4 categolies.</p>`
			`<div>`
			`<dl>`

			`<h3>connection-options</h3>`
			`<p>Parameters to connect PostgreSQL.</p>`

			`<div>`
			`<dl>`
			`<dt><tt>-h <tt><i>host</i></tt><br />`
			`<tt>--host <tt><i>host</i></tt></dt>`
			`<dd>Specifies the host name of the machine on which the server is running. If the value begins with a slash, it is used as the directory for the Unix domain socket. </dd>`

			`<dt><tt>-p <tt><i>port</i></tt><br />`
			`<tt>--port <tt><i>port</i></tt></dt>`
			`<dd>Specifies the TCP port or local Unix domain socket file extension on which the server is listening for connections.</dd>`

			`<dt><tt>-U <tt><i>username</i></tt><br />`
			`<tt>--username <tt><i>username</i></tt></dt>`
			`<dd>User name to connect as. </dd>`

			`<dt><tt>-W</tt><br /><tt>--password</tt></dt>`
			`<dd>Force pg_reorg to prompt for a password before connecting to a database.</dd>`
			`<dd>This option is never essential, since pg_reorg will automatically prompt for a password if the server demands password authentication. However, vacuumdb will waste a connection attempt finding out that the server wants a password. In some cases it is worth typing <tt>-W</tt> to avoid the extra connection attempt. </dd>`
			`</dl>`
			`</div>`

			`<h3>message-options</h3>`
			`<p>Specifies message output by pg_reorg.`
			`<tt>--quiet</tt> is ignored if some of the other options are specified.</p>`

			`<dl>`
			`<dt><tt>-e</tt><br /><tt>--echo</tt></dt>`
			`<dd>Echo the commands that pg_reorg generates and sends to the server.</dd>`
			`<dt><tt>-q</tt><br /><tt>--quiet</tt></dt>`
			`<dd>Do not display progress messages. </dd>`
			`<dt><tt>-v</tt><br /><tt>--verbose</tt></dt>`
			`<dd>Print detailed information during processing.</dd>`
			`</dl>`

			`<h3>order-options</h3>`
			`<p>Options to order rows.`
			`If not specified, pg_reorg do online CLUSTER using cluster indexes.`
			`Only one option can be specified.`
			`</p>`

			`<dl>`
			`<dt><tt>-n</tt><br /><tt>--no-order</tt></dt>`
			`<dd>Do online VACUUM FULL.</dd>`

			`<dt><tt>-o</tt> <tt><i>columns [,...]</i></tt><br />`
			`<tt>--order-by</tt> <tt><i>columns [,...]</i></tt></dt>`
			`<dd>Do online CLUSTER ordered by specified columns.</dd>`
			`</dl>`


			`<h3>target-options</h3>`
			`<p>`
			`Options to specify target tables or databases.`
			`You cannot use <tt>--all</tt> and <tt>--dbname</tt> or <tt>--table</tt> together.`
			`</p>`

			`<dl>`
			`<dt><tt>-a</tt><br /><tt>--all</tt></dt>`
			`<dd>Reorganize all databases.</dd>`

			`<dt>`
			`<tt>-d <tt><i>dbname</i></tt><br />`
			`<tt>--dbname <tt><i>dbname</i></tt>`
			`</dt>`
			`<dd>Specifies the name of the database to be reorganized. If this is not specified and <tt>-a</tt> (or <tt>--all</tt>) is not used, the database name is read from the environment variable <tt>PGDATABASE</tt>. If that is not set, the user name specified for the connection is used. </dd>`

			`<dt>`
			`<tt>-t</tt> <tt><i>table</i></tt><br />`
			`<tt>--table</tt> <tt><i>table</i></tt>`
			`</dt>`
			`<dd>Reorganize <tt><i>table</i></tt> only. If you don't specify this option, all tables in specified databases are reorganized.</dd>`
			`</dl>`
			`</div>`

			`<div><a name="environment"></a>`
			`<h2>Environment</h2> <div>`
			`<dl>`
			`<dt>`
			`<tt>PGDATABASE</tt><br />`
			`<tt>PGHOST</tt><br />`
			`<tt>PGPORT</tt><br />`
			`<tt>PGUSER</tt>`
			`</dt>`
			`<dd>Default connection parameters</dd>`
			`</dl>`
			`</div>`
			`<p>This utility, like most other PostgreSQL utilities, also uses the environment variables supported by libpq (see <a href="http://developer.postgresql.org/pgdocs/postgres/libpq-envars.html">Environment Variables</a>).</p>`
			`</div>`

			`<div><a name="diagnostics"></a>`
			`<h2>Diagnostics</h2>`
			`<p>Error messages are reported when pg_reorg fails.`
			`The following list shows the cause of errors.</p>`
			`<p>You need to cleanup by hand after fatal erros.`
			`To cleanup, execute $PGHOME/share/contrib/uninstall_pg_reorg.sql to the database where the error occured and then execute $PGHOME/share/contrib/pg_reorg.sql. (Do uninstall and reinstall.)</p>`

			`<dl>`
			`<dt>pg_reorg : reorg database "template1" ... skipped</dt>`
			`<dd>pg_reorg is not installed in the database when <tt>--all</tt> option is specified.</dd>`
			`<dd>Do register pg_reorg to the database.</dd>`

			`<dt>ERROR: pg_reorg is not installed</dt>`
			`<dd>pg_reorg is not installed in the database specified by <tt>--dbname</tt>.</dd>`
			`<dd>Do register pg_reorg to the database.</dd>`

			`<dt>ERROR: relation "table" has no primary key</dt>`
			`<dd>The target table doesn't have PRIMARY KEY.</dd>`
			`<dd>Define PRIMARY KEY to the table. (ALTER TABLE ADD PRIMARY KEY)</dd>`

			`<dt>ERROR: relation "table" has no cluster key</dt>`
			`<dd>The target table doesn't have CLUSTER KEY.</dd>`
			`<dd>Define CLUSTER KEY to the table. (ALTER TABLE CLUSTER)</dd>`

			`<dt>pg_reorg : query failed: ERROR: column "col" does not exist</dt>`
			`<dd>The target table doesn't have columns specified by <tt>--order-by</tt> option.</dd>`
			`<dd>Specify existing columns.</dd>`

			`<dt>ERROR: permission denied for schema reorg</dt>`
			`<dd>Permission error.</dd>`
			`<dd>pg_reorg must be executed by superusers.</dd>`

			`<dt>pg_reorg : query failed: ERROR: trigger "z_reorg_trigger" for relation "tbl" already exists</dt>`
			`<dd>The target table already has a trigger named "z_reorg_trigger".</dd>`
			`<dd>Delete or rename the trigger.</dd>`

			`<dt>pg_reorg : trigger conflicted for tbl</dt>`
			`<dd>The target table already has a trigger which follows by "z_reorg_trigger" in alphabetical order.</dd>`
			`<dd>Delete or rename the trigger.</dd>`
			`</dl>`
			`</div>`

			`<div><a name="restrictions"></a>`
			`<h2>Restrictions</h2>`
			`<p>pg_reorg has the following restrictions.`
			`Be careful to avoid data corruptions.</p>`

			`<h3>Temp tables</h3>`
			`<p>pg_reorg cannot reorganize temp tables.</p>`

			`<h3>GiST indexes</h3>`
			`<p>pg_reorg cannot reorganize tables using GiST indexes.</p>`

			`<h3>DDL commands</h3>`
			`<p>You cannot do DDL commands <strong>except</strong> <tt>VACUUM</tt> and <tt>ANALYZE</tt> during pg_reorg.`
			`In many case pg_reorg would fail and rollback collectly, but there are some cases ending with data-corruption .</p>`

			`<dl>`
			`<dt><tt>TRUNCATE</tt></dt>`
			`<dd><tt>TRUNCATE</tt> is lost. Deleted rows still exist after pg_reorg.</dd>`

			`<dt><tt>CREATE INDEX</tt></dt>`
			`<dd>It causes index corruptions.</dd>`

			`<dt><tt>ALTER TABLE ... ADD COLUMN</tt></dt>`
			`<dd>It causes lost of data. Newly added columns are initialized with NULLs.</dd>`

			`<dt><tt>ALTER TABLE ... ALTER COLUMN TYPE</tt></dt>`
			`<dd>It causes data corruptions.</dd>`

			`<dt><tt>ALTER TABLE ... SET TABLESPACE</tt></dt>`
			`<dd>It causes data corruptions by wrong relfilenode.</dd>`
			`</dl>`
			`</div>`

			`<div><a name="install"></a>`
			`<h2>Installations</h2>`
			`<p>pg_reorg can be installed like standard contrib modules.</p>`
			`<h3>Build from source</h3>`
			`<p>Place pg_reorg to $PGHOME/contrib/ and input make, make install.</p>`
			`<h3>Register to database</h3>`
			`<p>Start PostgreSQL and execute pg_reorg.sql in $PGHOME/share/contrib.</p>`
			`</div>`

			`<div><a name="requirement"></a>`
			`<h2>Requirements</h2>`
			`<dl>`
			`<dt>PostgreSQL version</dt><dd>PostgreSQL 8.3</dd>`
			`<dt>OS</dt><dd>RHEL 5.2, Windows XP SP3</dd>`
			`<dt>Disks</dt><dd>Requires amount of disks twice larger than target table and indexes.</dd>`
			`</dl>`
			`</div>`

			`<div><a name="seealso"></a>`
			`<h2>See Also</h2>`
			`<a href="http://developer.postgresql.org/pgdocs/postgres/app-clusterdb.html"><i><tt>clusterdb</tt></i></a>,`
			`<a href="http://developer.postgresql.org/pgdocs/postgres/app-vacuumdb.html"><i><tt>vacuumdb</tt></i></a>`
			`</div>`

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