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More cross-reference work, other minor SGML fixes and improvements.

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This commit is contained in:
Neil Conway 2004-03-26 03:18:28 +00:00
parent fda3449625
commit 1090aa8cc7
3 changed files with 107 additions and 64 deletions
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43
doc/src/sgml/monitoring.sgml
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@ -1,5 +1,5 @@
<!--
$PostgreSQL: pgsql/doc/src/sgml/monitoring.sgml,v 1.25 2003/11/29 19:51:37 pgsql Exp $
$PostgreSQL: pgsql/doc/src/sgml/monitoring.sgml,v 1.26 2004/03/26 03:18:28 neilc Exp $
-->
<chapter id="monitoring">
@ -28,7 +28,8 @@ $PostgreSQL: pgsql/doc/src/sgml/monitoring.sgml,v 1.25 2003/11/29 19:51:37 pgsql
but one should not neglect regular Unix monitoring programs such as
<command>ps</> and <command>top</>. Also, once one has identified a
poorly-performing query, further investigation may be needed using
<productname>PostgreSQL</productname>'s <command>EXPLAIN</> command.
<productname>PostgreSQL</productname>'s <xref linkend="sql-explain"
endterm="sql-explain-title"> command.
<xref linkend="using-explain"> discusses <command>EXPLAIN</>
and other methods for understanding the behavior of an individual
query.
@ -126,28 +127,30 @@ postgres: <replaceable>user</> <replaceable>database</> <replaceable>host</> <re
</para>
<para>
The parameter <varname>stats_start_collector</varname> must be set to
<literal>true</> for the statistics collector to
be launched at all. This is the default and recommended setting,
but it may be turned off if you have no interest in statistics and
want to squeeze out every last drop of overhead. (The savings is
likely to be small, however.) Note that this option
cannot be changed while the server is running.
The parameter <xref linkend="guc-stats-start-collector"> must be
set to <literal>true</> for the statistics collector to be launched
at all. This is the default and recommended setting, but it may be
turned off if you have no interest in statistics and want to
squeeze out every last drop of overhead. (The savings is likely to
be small, however.) Note that this option cannot be changed while
the server is running.
</para>
<para>
The parameters <varname>stats_command_string</varname>,
<varname>stats_block_level</varname>,
and <varname>stats_row_level</varname> control how much information is
The parameters <xref linkend="guc-stats-command-string">,
<xref linkend="guc-stats-block-level">, and <xref
linkend="guc-stats-row-level"> control how much information is
actually sent to the collector and thus determine how much run-time
overhead occurs. These respectively determine whether a server process
sends its current command string, disk-block-level access statistics, and
row-level access statistics to the collector. Normally these parameters are
set in <filename>postgresql.conf</> so that they apply to all server
processes, but it is possible to turn them on or off in individual sessions
using the <command>SET</> command. (To prevent ordinary users
from hiding their activity from the administrator, only superusers are
allowed to change these parameters with <command>SET</>.)
overhead occurs. These respectively determine whether a server
process sends its current command string, disk-block-level access
statistics, and row-level access statistics to the collector.
Normally these parameters are set in <filename>postgresql.conf</>
so that they apply to all server processes, but it is possible to
turn them on or off in individual sessions using the <xref
linkend="sql-set" endterm="sql-set-title"> command. (To prevent
ordinary users from hiding their activity from the administrator,
only superusers are allowed to change these parameters with
<command>SET</>.)
</para>
<note>

5
doc/src/sgml/plpgsql.sgml
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@ -1,5 +1,5 @@
<!--
$PostgreSQL: pgsql/doc/src/sgml/plpgsql.sgml,v 1.36 2004/02/27 03:59:23 neilc Exp $
$PostgreSQL: pgsql/doc/src/sgml/plpgsql.sgml,v 1.37 2004/03/26 03:18:28 neilc Exp $
-->
<chapter id="plpgsql">
@ -128,7 +128,8 @@ END;
<para>
The <application>PL/pgSQL</application>
<command>EXECUTE</command> statement is not related to the
<command>EXECUTE</command> statement supported by the
<xref linkend="sql-execute" endterm="sql-execute-title"> SQL
statement supported by the
<productname>PostgreSQL</productname> server. The server's
<command>EXECUTE</command> statement cannot be used within
<application>PL/pgSQL</> functions (and is not needed).

123
doc/src/sgml/runtime.sgml
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@ -1,5 +1,5 @@
<!--
$PostgreSQL: pgsql/doc/src/sgml/runtime.sgml,v 1.254 2004/03/24 22:40:28 tgl Exp $
$PostgreSQL: pgsql/doc/src/sgml/runtime.sgml,v 1.255 2004/03/26 03:18:28 neilc Exp $
-->
<Chapter Id="runtime">
@ -521,12 +521,14 @@ env PGOPTIONS='-c geqo=off' psql
Furthermore, it is possible to assign a set of option settings to
a user or a database. Whenever a session is started, the default
settings for the user and database involved are loaded. The
commands <command>ALTER DATABASE</command> and <command>ALTER
USER</command>, respectively, are used to configure these
settings. Per-database settings override anything received
from the <command>postmaster</command> command-line or the
configuration file, and in turn are overridden by per-user
settings; both are overridden by per-session options.
commands <xref linkend="sql-alterdatabase"
endterm="sql-alterdatabase-title"> and <xref
linkend="sql-alteruser" endterm="sql-alteruser-title">,
respectively, are used to configure these settings. Per-database
settings override anything received from the
<command>postmaster</command> command-line or the configuration
file, and in turn are overridden by per-user settings; both are
overridden by per-session options.
</para>
<para>
@ -652,7 +654,7 @@ SET ENABLE_SEQSCAN TO OFF;
server is to listen for
connections from client applications. The default is normally
<filename>/tmp</filename>, but can be changed at build time.
This parameter can only be set at server start.
This parameter can only be set at server start.
</para>
</listitem>
</varlistentry>
@ -711,10 +713,11 @@ SET ENABLE_SEQSCAN TO OFF;
<term><varname>rendezvous_name</varname> (<type>string</type>)</term>
<listitem>
<para>
Specifies the Rendezvous broadcast name. By default, the
computer name is used, specified as an empty string ''.
This option is only meaningful on platforms that support Rendezvous.
This option can only be set at server start.
Specifies the <productname>Rendezvous</productname> broadcast
name. By default, the computer name is used, specified as an
empty string ''. This option is only meaningful on platforms
that support <productname>Rendezvous</productname>. This
option can only be set at server start.
</para>
</listitem>
</varlistentry>
@ -759,10 +762,13 @@ SET ENABLE_SEQSCAN TO OFF;
<term><varname>password_encryption</varname> (<type>boolean</type>)</term>
<listitem>
<para>
When a password is specified in <command>CREATE USER</> or
<command>ALTER USER</> without writing either <literal>ENCRYPTED</> or
<literal>UNENCRYPTED</>, this option determines whether the password is to be
encrypted. The default is on (encrypt the password).
When a password is specified in <xref
linkend="sql-createuser" endterm="sql-createuser-title"> or
<xref linkend="sql-alteruser" endterm="sql-alteruser-title">
without writing either <literal>ENCRYPTED</> or
<literal>UNENCRYPTED</>, this option determines whether the
password is to be encrypted. The default is on (encrypt the
password).
</para>
</listitem>
</varlistentry>
@ -1010,13 +1016,14 @@ SET ENABLE_SEQSCAN TO OFF;
<title>Cost-Based Vacuum Delay</title>
<para>
During the execution of <command>VACUUM</command>
and <command>ANALYZE</command> commands,
the system maintains an internal counter that keeps track of the
estimated cost of the various I/O operations that are performed.
When the accumulated cost reaches a limit
(specified by <varname>vacuum_cost_limit</varname>), the process
performing the operation will sleep for a while (specified by
During the execution of <xref linkend="sql-vacuum"
endterm="sql-vacuum-title"> and <xref linkend="sql-analyze"
endterm="sql-analyze-title"> commands, the system maintains an
internal counter that keeps track of the estimated cost of the
various I/O operations that are performed. When the accumulated
cost reaches a limit (specified by
<varname>vacuum_cost_limit</varname>), the process performing
the operation will sleep for a while (specified by
<varname>vacuum_cost_naptime</varname>). Then it will reset the
counter and continue execution.
</para>
@ -1306,10 +1313,13 @@ SET ENABLE_SEQSCAN TO OFF;
choose a better plan. Other ways to improve the quality of the
plans chosen by the optimizer include configuring the <xref
linkend="runtime-config-query-constants"
endterm="runtime-config-query-constants-title">, running
<command>ANALYZE</command> more frequently, and increasing the
amount of statistics collected for a particular column using
<command>ALTER TABLE SET STATISTICS</command>.
endterm="runtime-config-query-constants-title">, running <xref
linkend="sql-analyze" endterm="sql-analyze-title"> more
frequently, increasing the value of the <xref
linkend="guc-default-statistics-target"> configuration parameter,
and increasing the amount of statistics collected for a
particular column using <command>ALTER TABLE SET
STATISTICS</command>.
</para>
</note>
@ -2115,13 +2125,27 @@ SET ENABLE_SEQSCAN TO OFF;
<term><varname>log_statement</varname> (<type>boolean</type>)</term>
<listitem>
<para>
Causes each SQL statement to be logged. The default is off.
<command>EXECUTE</> only displays the plan name, not the
prepared query. Server-side languages like
<application>PL/pgSQL</> that store functions in a cache only
display their queries on first function call. Only superusers can
turn off this option if it is enabled by the administrator.
Causes each SQL statement to be logged. The default is
off. Only superusers can disable this option if it has been
enabled by an administrator.
</para>
<note>
<para>
When the <command>EXECUTE</command> statement is logged, only
the name of the prepared statement is recorded, not the
entire prepared statement.
</para>
<para>
When a function is defined in a server-side language like
<application>PL/pgSQL</application>, any queries executed by
the function will only be logged the first time that the
function is invoked in a particular session. This is because
the <application>PL/pgSQL</application> keeps a cache of the
query plans produced for the SQL statements in the function.
</para>
</note>
</listitem>
</varlistentry>
@ -2202,14 +2226,27 @@ SET ENABLE_SEQSCAN TO OFF;
</listitem>
</varlistentry>
<varlistentry>
<varlistentry id="guc-stats-block-level" xreflabel="guc_stats_block_level">
<term><varname>stats_block_level</varname> (<type>boolean</type>)</term>
<listitem>
<para>
Enables the collection of block-level statistics on database
activity. This option is disabled by default. If this option
is enabled, the data that is produced can be accessed via the
<structname>pg_stat</structname> and
<structname>pg_statio</structname> family of system views;
refer to <xref linkend="monitoring"> for more information.
</para>
</listitem>
</varlistentry>
<varlistentry id="guc-stats-row-level" xreflabel="guc_stats_row_level">
<term><varname>stats_row_level</varname> (<type>boolean</type>)</term>
<listitem>
<para>
These enable the collection of block-level and row-level statistics
on database activity, respectively. These options are off by
default. This data can be accessed via the
Enables the collection of row-level statistics on database
activity. This option is disabled by default. If this option
is enabled, the data that is produced can be accessed via the
<structname>pg_stat</structname> and
<structname>pg_statio</structname> family of system views;
refer to <xref linkend="monitoring"> for more information.
@ -2311,10 +2348,12 @@ SET ENABLE_SEQSCAN TO OFF;
<term><varname>check_function_bodies</varname> (<type>boolean</type>)</term>
<listitem>
<para>
This parameter is normally true. When set false, it disables
validation of the function body string in <command>CREATE FUNCTION</>.
Disabling validation is occasionally useful to avoid problems such as
forward references when restoring function definitions from a dump.
This parameter is normally true. When set to false, it disables
validation of the function body string in <xref
linkend="sql-createfunction"
endterm="sql-createfunction-title">. Disabling validation is
occasionally useful to avoid problems such as forward
references when restoring function definitions from a dump.
</para>
</listitem>
</varlistentry>
@ -2503,7 +2542,7 @@ SET ENABLE_SEQSCAN TO OFF;
<listitem>
<para>
Sets the locale to use for formatting numbers, for example
with the <function>to_char()</function> family of
with the <function>to_char</function> family of
functions. Acceptable values are system-dependent; see <xref
linkend="locale"> for more information. If this variable is
set to the empty string (which is the default) then the value