diff options
Diffstat (limited to 'doc/src/sgml/ref')
| -rw-r--r-- | doc/src/sgml/ref/alter_table.sgml | 26 | ||||
| -rw-r--r-- | doc/src/sgml/ref/cluster.sgml | 31 | ||||
| -rw-r--r-- | doc/src/sgml/ref/clusterdb.sgml | 4 | ||||
| -rw-r--r-- | doc/src/sgml/ref/reindex.sgml | 44 | ||||
| -rw-r--r-- | doc/src/sgml/ref/set_session_auth.sgml | 32 | ||||
| -rw-r--r-- | doc/src/sgml/ref/vacuum.sgml | 10 |
6 files changed, 99 insertions, 48 deletions
diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml index 5499cd158cc..2b084456013 100644 --- a/doc/src/sgml/ref/alter_table.sgml +++ b/doc/src/sgml/ref/alter_table.sgml @@ -1,5 +1,5 @@ <!-- -$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_table.sgml,v 1.55 2003/02/13 05:19:59 momjian Exp $ +$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_table.sgml,v 1.56 2003/02/19 04:06:28 momjian Exp $ PostgreSQL documentation --> @@ -367,7 +367,7 @@ ALTER TABLE <replaceable class="PARAMETER">table</replaceable> default and NOT NULL clauses for the new column are not supported. The new column always comes into being with all values NULL. You can use the <literal>SET DEFAULT</literal> form - of <command>ALTER TABLE</command> to set the default afterwards. + of <command>ALTER TABLE</command> to set the default afterward. (You may also want to update the already existing rows to the new default value, using <xref linkend="sql-update" endterm="sql-update-title">.) @@ -392,19 +392,21 @@ VACUUM FULL table; </para> <para> - If a table has any descendant tables, it is not permitted to ADD or - RENAME a column in the parent table without doing the same to the - descendants --- that is, ALTER TABLE ONLY will be rejected. This - ensures that the descendants always have columns matching the parent. + If a table has any descendant tables, it is not permitted to ADD + or RENAME a column in the parent table without doing the same to + the descendants --- that is, <command>ALTER TABLE ONLY</command> + will be rejected. This ensures that the descendants always have + columns matching the parent. </para> <para> - A recursive DROP COLUMN operation will remove a descendant table's column - only if the descendant does not inherit that column from any other - parents and never had an independent definition of the column. - A nonrecursive DROP COLUMN (i.e., ALTER TABLE ONLY ... DROP COLUMN) - never removes any descendant columns, but instead marks them as - independently defined rather than inherited. + A recursive <literal>DROP COLUMN</literal> operation will remove a + descendant table's column only if the descendant does not inherit + that column from any other parents and never had an independent + definition of the column. A nonrecursive <literal>DROP + COLUMN</literal> (i.e., <command>ALTER TABLE ONLY ... DROP + COLUMN</command>) never removes any descendant columns, but + instead marks them as independently defined rather than inherited. </para> <para> diff --git a/doc/src/sgml/ref/cluster.sgml b/doc/src/sgml/ref/cluster.sgml index 95daa8bf176..1c3874c8d1a 100644 --- a/doc/src/sgml/ref/cluster.sgml +++ b/doc/src/sgml/ref/cluster.sgml @@ -1,5 +1,5 @@ <!-- -$Header: /cvsroot/pgsql/doc/src/sgml/ref/cluster.sgml,v 1.23 2002/12/30 18:42:12 tgl Exp $ +$Header: /cvsroot/pgsql/doc/src/sgml/ref/cluster.sgml,v 1.24 2003/02/19 04:06:28 momjian Exp $ PostgreSQL documentation --> @@ -117,11 +117,19 @@ CLUSTER <command>CLUSTER</command> without any parameter re-clusters all the tables in the current database that the calling user owns, or all tables if called - by a superuser. (Never-clustered tables are not touched.) This + by a superuser. (Never-clustered tables are not included.) This form of <command>CLUSTER</command> cannot be called from inside a transaction or function. </para> + <para> + When a table is being clustered, an <literal>ACCESS + EXCLUSIVE</literal> lock is acquired on it. This prevents any other + database operations (both reads and writes) from preceding on the + table until the <command>CLUSTER</command> is finished. See the + &cite-user; for more information on database locking. + </para> + <refsect2 id="R2-SQL-CLUSTER-3"> <refsect2info> <date>1998-09-08</date> @@ -159,8 +167,9 @@ CLUSTER </para> <para> - <command>CLUSTER</command> preserves GRANT, inheritance, index, foreign - key, and other ancillary information about the table. + <command>CLUSTER</command> preserves <command>GRANT</command>, + inheritance, index, foreign key, and other ancillary information + about the table. </para> <para> @@ -212,13 +221,15 @@ SELECT <replaceable class="parameter">columnlist</replaceable> INTO TABLE <repla Usage </title> <para> - Cluster the employees relation on the basis of its ID attribute: + Cluster the <literal>employees</literal> relation on the basis of + its ID attribute: </para> <programlisting> CLUSTER emp_ind ON emp; </programlisting> <para> - Cluster the employees relation using the same index that was used before: + Cluster the <literal>employees</literal> relation using the same + index that was used before: </para> <programlisting> CLUSTER emp; @@ -248,6 +259,14 @@ CLUSTER; </para> </refsect2> </refsect1> + + <refsect1> + <title>See Also</title> + + <simplelist type="inline"> + <member><xref linkend="app-clusterdb" endterm="app-clusterdb-title"></member> + </simplelist> + </refsect1> </refentry> <!-- Keep this comment at the end of the file diff --git a/doc/src/sgml/ref/clusterdb.sgml b/doc/src/sgml/ref/clusterdb.sgml index 1b8f9ba331a..4a158f334c8 100644 --- a/doc/src/sgml/ref/clusterdb.sgml +++ b/doc/src/sgml/ref/clusterdb.sgml @@ -1,5 +1,5 @@ <!-- -$Header: /cvsroot/pgsql/doc/src/sgml/ref/clusterdb.sgml,v 1.6 2003/02/13 05:37:43 momjian Exp $ +$Header: /cvsroot/pgsql/doc/src/sgml/ref/clusterdb.sgml,v 1.7 2003/02/19 04:06:28 momjian Exp $ PostgreSQL documentation --> @@ -37,7 +37,7 @@ PostgreSQL documentation in a <productname>PostgreSQL</productname> database. It finds tables that have previously been clustered, and clusters them again on the same index that was last used. Tables that have never been clustered are not - touched. + affected. </para> <para> diff --git a/doc/src/sgml/ref/reindex.sgml b/doc/src/sgml/ref/reindex.sgml index 08666b2f02a..e146fe53928 100644 --- a/doc/src/sgml/ref/reindex.sgml +++ b/doc/src/sgml/ref/reindex.sgml @@ -1,5 +1,5 @@ <!-- -$Header: /cvsroot/pgsql/doc/src/sgml/ref/reindex.sgml,v 1.14 2002/11/17 23:43:32 momjian Exp $ +$Header: /cvsroot/pgsql/doc/src/sgml/ref/reindex.sgml,v 1.15 2003/02/19 04:06:28 momjian Exp $ PostgreSQL documentation --> @@ -38,8 +38,9 @@ REINDEX { DATABASE | TABLE | INDEX } <replaceable class="PARAMETER">name</replac <term>DATABASE</term> <listitem> <para> - Recreate all system indexes of a specified database. - (User-table indexes are not included.) + Recreate all system indexes of a specified database. Indexes on + user tables are not included. This form of <command>REINDEX</> can + only be used in standalone mode (see below). </para> </listitem> </varlistentry> @@ -116,16 +117,35 @@ REINDEX Description </title> <para> - <command>REINDEX</command> is used to rebuild corrupted indexes. - Although in theory this should never be necessary, in practice - indexes may become corrupted due to software bugs or hardware - failures. <command>REINDEX</command> provides a recovery method. - </para> + <command>REINDEX</command> rebuilds an index based on the data + stored in the table, replacing the old copy of the index. There are + two main reasons to use <command>REINDEX</command>: - <para> - <command>REINDEX</command> also removes certain dead index pages that - can't be reclaimed any other way. See the "Routine Reindexing" - section in the manual for more information. + <orderedlist> + <listitem> + <para> + An index has become corrupted, and no longer contains valid + data. Although in theory this should never be necessary, in + practice indexes may become corrupted due to software bugs or + hardware failures. <command>REINDEX</command> provides a + recovery method. + </para> + </listitem> + + <listitem> + <para> + The index in question contains a lot of dead index pages that + are not being reclaimed. This can occur with B+-tree indexes + under certain access patterns. <command>REINDEX</command> + provides a way to reduce the space consumption of the index by + writing a new version of the index without the dead pages. See + the <quote>Routine Reindexing</quote> section in the + &cite-admin; for more information. The rest of this section + mostly discusses how to use <command>REINDEX</command> to + recover from index corruption. + </para> + </listitem> + </orderedlist> </para> <para> diff --git a/doc/src/sgml/ref/set_session_auth.sgml b/doc/src/sgml/ref/set_session_auth.sgml index eb9d760f10e..88d5578498c 100644 --- a/doc/src/sgml/ref/set_session_auth.sgml +++ b/doc/src/sgml/ref/set_session_auth.sgml @@ -1,4 +1,4 @@ -<!-- $Header: /cvsroot/pgsql/doc/src/sgml/ref/set_session_auth.sgml,v 1.7 2002/09/21 18:32:54 petere Exp $ --> +<!-- $Header: /cvsroot/pgsql/doc/src/sgml/ref/set_session_auth.sgml,v 1.8 2003/02/19 04:06:28 momjian Exp $ --> <refentry id="SQL-SET-SESSION-AUTHORIZATION"> <docinfo> <date>2001-04-21</date> @@ -16,7 +16,7 @@ <refsynopsisdiv> <synopsis> -SET [ SESSION | LOCAL ] SESSION AUTHORIZATION <parameter>username</parameter> +SET [ SESSION | LOCAL ] SESSION AUTHORIZATION <replaceable class="PARAMETER">username</replaceable> SET [ SESSION | LOCAL ] SESSION AUTHORIZATION DEFAULT RESET SESSION AUTHORIZATION </synopsis> @@ -27,12 +27,12 @@ RESET SESSION AUTHORIZATION <para> This command sets the session user identifier and the current user - identifier of the current SQL-session context to be - <parameter>username</parameter>. The user name may be written as - either an identifier or a string literal. - The session user identifier is valid for the duration of a - connection; for example, it is possible to temporarily become an - unprivileged user and later switch back to become a superuser. + identifier of the current SQL-session context to be <replaceable + class="PARAMETER">username</replaceable>. The user name may be + written as either an identifier or a string literal. The session + user identifier is valid for the duration of a connection; for + example, it is possible to temporarily become an unprivileged user + and later switch back to become a superuser. </para> <para> @@ -68,19 +68,21 @@ RESET SESSION AUTHORIZATION <refsect1> <title>Examples</title> -<screen> -<userinput>SELECT SESSION_USER, CURRENT_USER;</userinput> - current_user | session_user +<programlisting> +SELECT SESSION_USER, CURRENT_USER; + + session_user | current_user --------------+-------------- peter | peter -<userinput>SET SESSION AUTHORIZATION 'paul';</userinput> +SET SESSION AUTHORIZATION 'paul'; + +SELECT SESSION_USER, CURRENT_USER; -<userinput>SELECT SESSION_USER, CURRENT_USER;</userinput> - current_user | session_user + session_user | current_user --------------+-------------- paul | paul -</screen> +</programlisting> </refsect1> <refsect1> diff --git a/doc/src/sgml/ref/vacuum.sgml b/doc/src/sgml/ref/vacuum.sgml index 07dbbaed2a7..b8ab33cbe4a 100644 --- a/doc/src/sgml/ref/vacuum.sgml +++ b/doc/src/sgml/ref/vacuum.sgml @@ -1,5 +1,5 @@ <!-- -$Header: /cvsroot/pgsql/doc/src/sgml/ref/vacuum.sgml,v 1.28 2003/01/19 00:13:31 momjian Exp $ +$Header: /cvsroot/pgsql/doc/src/sgml/ref/vacuum.sgml,v 1.29 2003/02/19 04:06:28 momjian Exp $ PostgreSQL documentation --> @@ -286,6 +286,14 @@ VACUUM </para> </refsect2> </refsect1> + + <refsect1> + <title>See Also</title> + + <simplelist type="inline"> + <member><xref linkend="app-vacuumdb" endterm="app-vacuumdb-title"></member> + </simplelist> + </refsect1> </refentry> <!-- Keep this comment at the end of the file |