diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/ref/lock.sgml | 254 | ||||
| -rw-r--r-- | doc/src/sgml/ref/set.sgml | 855 |
2 files changed, 589 insertions, 520 deletions
diff --git a/doc/src/sgml/ref/lock.sgml b/doc/src/sgml/ref/lock.sgml index eb3ad5fc53e..02245c1bfa3 100644 --- a/doc/src/sgml/ref/lock.sgml +++ b/doc/src/sgml/ref/lock.sgml @@ -1,84 +1,156 @@ -<REFENTRY ID="SQL-LOCK"> - <REFMETA> - <REFENTRYTITLE> +<refentry id="SQL-LOCK"> + <refmeta> + <refentrytitle> LOCK - </REFENTRYTITLE> - <REFMISCINFO>SQL - Language Statements</REFMISCINFO> - </REFMETA> - <REFNAMEDIV> - <REFNAME> + </refentrytitle> + <refmiscinfo>SQL - Language Statements</refmiscinfo> + </refmeta> + <refnamediv> + <refname> LOCK - </REFNAME> - <REFPURPOSE> + </refname> + <refpurpose> Explicit lock of a table inside a transaction - </REFPURPOSE> + </refpurpose> </refnamediv> - <REFSYNOPSISDIV> - <REFSYNOPSISDIVINFO> - <DATE>1998-09-24</DATE> - </REFSYNOPSISDIVINFO> - <SYNOPSIS> - LOCK [ TABLE ] [IN [ROW|ACCESS] [SHARE|EXCLUSIVE] | [SHARE ROW EXCLUSIVE] MODE] - <REPLACEABLE CLASS="PARAMETER">table</REPLACEABLE> - </SYNOPSIS> + <refsynopsisdiv> + <refsynopsisdivinfo> + <date>1998-09-24</date> + </refsynopsisdivinfo> + <synopsis> +LOCK [ TABLE ] <replaceable class="PARAMETER">table</replaceable> +LOCK [ TABLE ] <replaceable class="PARAMETER">table</replaceable> IN [ ROW | ACCESS ] { SHARE | EXCLUSIVE } MODE +LOCK [ TABLE ] <replaceable class="PARAMETER">table</replaceable> IN SHARE ROW EXCLUSIVE MODE + </synopsis> - <REFSECT2 ID="R2-SQL-LOCK-1"> - <REFSECT2INFO> - <DATE>1998-09-01</DATE> - </REFSECT2INFO> - <TITLE> + <refsect2 id="R2-SQL-LOCK-1"> + <refsect2info> + <date>1998-09-01</date> + </refsect2info> + <title> Inputs - </TITLE> - <PARA> - </PARA> - <VARIABLELIST> - <VARLISTENTRY> - <TERM> - <REPLACEABLE CLASS="PARAMETER">table</REPLACEABLE> - </TERM> - <LISTITEM> - <PARA> - The name of an existing table to lock. - </para> - </listitem> - </varlistentry> - </VARIABLELIST> - - </REFSECT2> + </title> + <para> + + <variablelist> + <varlistentry> + <term> + <replaceable class="PARAMETER">table</replaceable> + </term> + <listitem> + <para> + The name of an existing table to lock. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term> + SHARE MODE + </term> + <listitem> + <para> + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term> + EXCLUSIVE MODE + </term> + <listitem> + <para> + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term> + ROW SHARE MODE + </term> + <listitem> + <para> + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term> + ROW EXCLUSIVE MODE + </term> + <listitem> + <para> + </para> + </listitem> + </varlistentry> - <REFSECT2 ID="R2-SQL-LOCK-2"> - <REFSECT2INFO> - <DATE>1998-09-24</DATE> - </REFSECT2INFO> - <TITLE> + <varlistentry> + <term> + ACCESS SHARE MODE + </term> + <listitem> + <para> + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term> + ACCESS EXCLUSIVE MODE + </term> + <listitem> + <para> + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term> + SHARE ROW EXCLUSIVE MODE + </term> + <listitem> + <para> + </para> + </listitem> + </varlistentry> + </variablelist> + </para> + </refsect2> + + <refsect2 id="R2-SQL-LOCK-2"> + <refsect2info> + <date>1998-09-24</date> + </refsect2info> + <title> Outputs - </TITLE> - <PARA> + </title> + <para> - <VARIABLELIST> - <TERM> - ERROR <REPLACEABLE CLASS="PARAMETER">table</REPLACEABLE>: Table does not exist. - </TERM> - <LISTITEM> - <PARA> - Message returned if <REPLACEABLE CLASS="PARAMETER">table</REPLACEABLE> + <variablelist> + <varlistentry> + <term> + ERROR <replaceable class="PARAMETER">table</replaceable>: Table does not exist. + </term> + <listitem> + <para> + Message returned if <replaceable class="PARAMETER">table</replaceable> does not exist. </para> </listitem> </varlistentry> - </VARIABLELIST> + </variablelist> </para> - </REFSECT2> - </REFSYNOPSISDIV> + </refsect2> + </refsynopsisdiv> - <REFSECT1 ID="R1-SQL-LOCK-1"> - <REFSECT1INFO> - <DATE>1998-09-24</DATE> - </REFSECT1INFO> - <TITLE> + <refsect1 id="R1-SQL-LOCK-1"> + <refsect1info> + <date>1998-09-24</date> + </refsect1info> + <title> Description - </TITLE> - <PARA> + </title> + <para> By default, <command>LOCK</command> locks in exclusive mode a table inside a transaction. Various options allow shared access, or row-level locking control. The classic use for this is @@ -112,13 +184,13 @@ </para> </note> - <REFSECT2 ID="R2-SQL-LOCK-3"> - <REFSECT2INFO> - <DATE>1998-09-24</DATE> - </REFSECT2INFO> - <TITLE> + <refsect2 id="R2-SQL-LOCK-3"> + <refsect2info> + <date>1998-09-24</date> + </refsect2info> + <title> Notes - </TITLE> + </title> <para> <command>LOCK</command> is a <productname>Postgres</productname> language extension. @@ -134,16 +206,16 @@ </para> </note> </para> - </REFSECT2> + </refsect2> </refsect1> - <REFSECT1 ID="R1-SQL-LOCK-2"> - <TITLE> + <refsect1 id="R1-SQL-LOCK-2"> + <title> Usage - </TITLE> - <PARA> - </PARA> - <ProgramListing> + </title> + <para> + </para> + <programlisting> --Explicit locking to prevent deadlock: -- BEGIN WORK; @@ -152,30 +224,30 @@ UPDATE films SET len = INTERVAL '100 minute' WHERE len = INTERVAL '117 minute'; COMMIT WORK; - </ProgramListing> + </programlisting> - </REFSECT1> + </refsect1> - <REFSECT1 ID="R1-SQL-LOCK-3"> - <TITLE> + <refsect1 id="R1-SQL-LOCK-3"> + <title> Compatibility - </TITLE> + </title> - <REFSECT2 ID="R2-SQL-LOCK-4"> - <REFSECT2INFO> - <DATE>1998-09-24</DATE> - </REFSECT2INFO> - <TITLE> + <refsect2 id="R2-SQL-LOCK-4"> + <refsect2info> + <date>1998-09-24</date> + </refsect2info> + <title> SQL92 - </TITLE> - <PARA> + </title> + <para> There is no <command>LOCK TABLE</command> in <acronym>SQL92</acronym>, which instead uses <command>SET TRANSACTION</command> to specify concurrency level on transactions. We support that too. </para> </refsect2> </refsect1> -</REFENTRY> +</refentry> <!-- Keep this comment at the end of the file Local variables: diff --git a/doc/src/sgml/ref/set.sgml b/doc/src/sgml/ref/set.sgml index 2b203e7698b..e44e4c273a4 100644 --- a/doc/src/sgml/ref/set.sgml +++ b/doc/src/sgml/ref/set.sgml @@ -1,42 +1,43 @@ -<REFENTRY ID="SQL-SET"> - <REFMETA> - <REFENTRYTITLE> +<refentry id="SQL-SET"> + <refmeta> + <refentrytitle> SET - </REFENTRYTITLE> - <REFMISCINFO>SQL - Language Statements</REFMISCINFO> - </REFMETA> - <REFNAMEDIV> - <REFNAME> + </refentrytitle> + <refmiscinfo>SQL - Language Statements</refmiscinfo> + </refmeta> + <refnamediv> + <refname> SET - </REFNAME> - <REFPURPOSE> + </refname> + <refpurpose> Set run-time parameters for session - </REFPURPOSE> + </refpurpose> </refnamediv> - <REFSYNOPSISDIV> - <REFSYNOPSISDIVINFO> - <DATE>1998-09-24</DATE> - </REFSYNOPSISDIVINFO> - <SYNOPSIS> -SET <REPLACEABLE CLASS="PARAMETER">variable</REPLACEABLE> { TO | = } { '<REPLACEABLE CLASS="PARAMETER">value</REPLACEABLE>' | DEFAULT } -SET TIME ZONE { '<REPLACEABLE CLASS="PARAMETER">timezone</REPLACEABLE>' | LOCAL }; - </SYNOPSIS> + <refsynopsisdiv> + <refsynopsisdivinfo> + <date>1998-09-24</date> + </refsynopsisdivinfo> + <synopsis> +SET <replaceable class="PARAMETER">variable</replaceable> { TO | = } { '<replaceable class="PARAMETER">value</replaceable>' | DEFAULT } +SET TIME ZONE { '<replaceable class="PARAMETER">timezone</replaceable>' | LOCAL | DEFAULT }; +SET TRANSACTION ISOLATION LEVEL { READ COMMITTED | SERIALIZED | DEFAULT } + </synopsis> - <REFSECT2 ID="R2-SQL-SET-1"> - <REFSECT2INFO> - <DATE>1998-09-24</DATE> - </REFSECT2INFO> - <TITLE> + <refsect2 id="R2-SQL-SET-1"> + <refsect2info> + <date>1998-09-24</date> + </refsect2info> + <title> Inputs - </TITLE> - <PARA> + </title> + <para> - <VARIABLELIST> - <VARLISTENTRY> - <TERM> - <REPLACEABLE CLASS="PARAMETER">variable</REPLACEABLE> - </TERM> - <LISTITEM> + <variablelist> + <varlistentry> + <term> + <replaceable class="PARAMETER">variable</replaceable> + </term> + <listitem> <para> Settable global parameter. </para> @@ -44,146 +45,222 @@ SET TIME ZONE { '<REPLACEABLE CLASS="PARAMETER">timezone</REPLACEABLE>' | LOCAL </varlistentry> <varlistentry> <term> - <REPLACEABLE CLASS="PARAMETER">value</REPLACEABLE> + <replaceable class="PARAMETER">value</replaceable> </term> <listitem> - <PARA> + <para> New value of parameter. </para> </listitem> </varlistentry> </variablelist> </para> + <para> The possible variables and allowed values are: - <VARIABLELIST> - <VARLISTENTRY> - <TERM> - DateStyle - </TERM> - <LISTITEM> - <PARA> + <variablelist> + <varlistentry> + <term> + CLIENT_ENCODING | NAMES + </term> + <listitem> + <para> + Sets the multi-byte client encoding - <VARIABLELIST> - <VARLISTENTRY> - <TERM> + <variablelist> + <varlistentry> + <term> + <replaceable class="parameter">value</replaceable> + </term> + <listitem> + <para> + Sets the multi-byte client encoding to + <replaceable class="parameter">value</replaceable>. + The specified encoding must be supported by the backend. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term> + DEFAULT + </term> + <listitem> + <para> + Sets the multi-byte client encoding. + </para> + </listitem> + </varlistentry> + </variablelist> + </para> + + <para> + This is only enabled if multi-byte was specified to configure. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term> + DateStyle + </term> + <listitem> + <para> + <variablelist> + <varlistentry> + <term> ISO - </TERM> - <LISTITEM> - <PARA> + </term> + <listitem> + <para> use ISO 8601-style dates and times </para> </listitem> </varlistentry> - <VARLISTENTRY> - <TERM> + <varlistentry> + <term> SQL - </TERM> - <LISTITEM> - <PARA> + </term> + <listitem> + <para> use Oracle/Ingres-style dates and times </para> </listitem> </varlistentry> - <VARLISTENTRY> - <TERM> + <varlistentry> + <term> Postgres - </TERM> - <LISTITEM> - <PARA> + </term> + <listitem> + <para> use traditional <productname>Postgres</productname> format </para> </listitem> </varlistentry> - <VARLISTENTRY> - <TERM> + <varlistentry> + <term> European - </TERM> - <LISTITEM> - <PARA> + </term> + <listitem> + <para> use dd/mm/yyyy for numeric date representations. </para> </listitem> </varlistentry> - <VARLISTENTRY> - <TERM> + <varlistentry> + <term> NonEuropean - </TERM> - <LISTITEM> - <PARA> + </term> + <listitem> + <para> use mm/dd/yyyy for numeric date representations. </para> </listitem> </varlistentry> - <VARLISTENTRY> - <TERM> + <varlistentry> + <term> German - </TERM> - <LISTITEM> - <PARA> + </term> + <listitem> + <para> use dd.mm.yyyy for numeric date representations. </para> </listitem> </varlistentry> - <VARLISTENTRY> - <TERM> + <varlistentry> + <term> US - </TERM> - <LISTITEM> - <PARA> + </term> + <listitem> + <para> same as 'NonEuropean' </para> </listitem> </varlistentry> - <VARLISTENTRY> - <TERM> + <varlistentry> + <term> default - </TERM> - <LISTITEM> - <PARA> + </term> + <listitem> + <para> restores the default values ('US,Postgres') </para> </listitem> </varlistentry> </variablelist> </para> + + <para> + Date format initialization my be done by: + <simplelist> + <member> + Setting PGDATESTYLE environment variable. + </member> + <member> + Running postmaster using -oe parameter to set + dates to the 'European' convention. + Note that this affects only the some combinations of date styles; for example + the ISO style is not affected by this parameter. + </member> + <member> + Changing variables in + <filename>src/backend/utils/init/globals.c</filename>. + </member> + </simplelist> + </para> + <para> + The variables in <filename>globals.c</filename> which can be changed are: + <simplelist> + <member> + bool EuroDates = false | true + </member> + <member> + int DateStyle = USE_ISO_DATES | USE_POSTGRES_DATES | USE_SQL_DATES | USE_GERMAN_DATES + </member> + </simplelist> + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term> + SERVER_ENCODING + </term> + <listitem> + <para> + Sets the multi-byte server encoding + + <variablelist> + <varlistentry> + <term> + <replaceable class="parameter">value</replaceable> + </term> + <listitem> + <para> + Sets the multi-byte server encoding. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term> + DEFAULT + </term> + <listitem> + <para> + Sets the multi-byte server encoding. + </para> + </listitem> + </varlistentry> + </variablelist> + </para> + <para> + This is only enabled if multi-byte was specified to configure. + </para> </listitem> </varlistentry> - </variablelist> - </para> - <para> - Date format initialization my be done by: - <simplelist> - <member> - Setting PGDATESTYLE environment variable. - </member> - <member> - Running postmaster using -oe parameter to set - dates to the 'European' convention. - Note that this affects only the some combinations of date styles; for example - the ISO style is not affected by this parameter. - </member> - <member> - Changing variables in - <filename>src/backend/utils/init/globals.c</filename>. - </member> - </simplelist> - </para> - <para> - The variables in <filename>globals.c</filename> which can be changed are: - <simplelist> - <member> - bool EuroDates = false | true - </member> - <member> - int DateStyle = USE_ISO_DATES | USE_POSTGRES_DATES | USE_SQL_DATES | USE_GERMAN_DATES - </member> - </simplelist> - </para> - <para> - <variablelist> <varlistentry> <term> TIMEZONE @@ -257,8 +334,59 @@ SET TIME ZONE { '<REPLACEABLE CLASS="PARAMETER">timezone</REPLACEABLE>' | LOCAL </para> </listitem> </varlistentry> + + <varlistentry> + <term> + TRANSACTION ISOLATION LEVEL + </term> + <listitem> + <para> + Sets the isolation level for the current transaction. + + <variablelist> + <varlistentry> + <term> + READ COMMITTED + </term> + <listitem> + <para> + The current transaction reads only + committed rows. READ COMMITTED is the default. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term> + SERIALIZABLE + </term> + <listitem> + <para> + The current transaction will place a + lock on every row read, so later reads in that transaction + see the rows unmodified by other transactions. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term> + DEFAULT + </term> + <listitem> + <para> + Sets the isolation level for the current transaction to + <option>READ COMMITTED</option>. + </para> + </listitem> + </varlistentry> + </variablelist> + </para> + </listitem> + </varlistentry> </variablelist> </para> + <para> There are also several internal or optimization parameters which can be specified @@ -301,295 +429,154 @@ SET TIME ZONE { '<REPLACEABLE CLASS="PARAMETER">timezone</REPLACEABLE>' | LOCAL The frontend may be initialized by setting the PGCOSTHEAP environment variable. </para> - <variablelist> - <varlistentry> - <term> - COST_INDEX - </term> - <listitem> - <para> - Sets the default cost of an index scan for use by the optimizer. - </para> - </listitem> - </varlistentry> - - <varlistentry> - <term> - <replaceable class="parameter">float4</replaceable> - </term> - <listitem> - <para> - Set the cost of an index scan to the specified floating point value. - </para> - </listitem> - </varlistentry> - - <varlistentry> - <term> - DEFAULT - </term> - <listitem> - <para> - Sets the cost of an index scan to the default value. - </para> - </listitem> - </varlistentry> - </variablelist> - </listitem> - </varlistentry> - </variablelist> - </para> - <para> - The frontend may be initialized by setting the PGCOSTINDEX - environment variable. - - <variablelist> - <varlistentry> - <term> - GEQO - </term> - <listitem> - <para> - Sets the threshold for using the genetic optimizer algorithm. - </para> - - <variablelist> - <varlistentry> - <term> - On - </term> - <listitem> - <para> - enables the genetic optimizer algorithm - for statements with 6 or more tables. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term> - On=<replaceable class="parameter">#</replaceable> - </term> - <listitem> - <para> - Takes an integer argument to enable the genetic optimizer algorithm - for statements with <replaceable class="parameter">#</replaceable> - or more tables in the query. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term> - Off - </term> - <listitem> - <para> - disables the genetic optimizer algorithm. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term> - DEFAULT - </term> - <listitem> - <para> - Equivalent to specifying <command>SET GEQO='on'</command> - </para> - </listitem> - </varlistentry> - </variablelist> </listitem> </varlistentry> - </variablelist> - </para> - <para> - This algorithm is on by default, which used GEQO for - statements of eleven or more tables. - (See the chapter on GEQO in the Programmer's Guide - for more information). - </para> - <para> - The frontend may be initialized by setting PGGEQO - environment variable. - </para> - <para> - It may be useful when joining big relations with - small ones. This algorithm is off by default. - It's not used by GEQO anyway. - - <variablelist> - <varlistentry> - <term> - KSQO - </term> - <listitem> - <para> - <firstterm>Key Set Query Optimizer</firstterm> forces the query optimizer - to optimize repetative OR clauses such as generated by - <productname>MicroSoft Access</productname>: - </para> - - <variablelist> - <varlistentry> - <term> - On - </term> - <listitem> - <para> - enables this optimization. - </para> - </listitem> - </varlistentry> - - <varlistentry> - <term> - Off - </term> - <listitem> - <para> - disables this optimization. - </para> - </listitem> - </varlistentry> - - <varlistentry> - <term> - DEFAULT - </term> - <listitem> - <para> - Equivalent to specifying <command>SET KSQO='off'</command>. - </para> - </listitem> - </varlistentry> - </variablelist> - </listitem> - </varlistentry> - </variablelist> - </para> - <para> - It may be useful when joining big relations with - small ones. This algorithm is off by default. - It's not used by GEQO anyway. - </para> - <para> - The frontend may be initialized by setting the PGKSQO - environment variable. - <variablelist> + <varlistentry> <term> - QUERY_LIMIT + COST_INDEX </term> <listitem> <para> - Sets the number of rows returned by a query. + Sets the default cost of an index scan for use by the optimizer. + + <variablelist> + <varlistentry> + <term> + <replaceable class="parameter">float4</replaceable> + </term> + <listitem> + <para> + Set the cost of an index scan to the specified floating point value. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term> + DEFAULT + </term> + <listitem> + <para> + Sets the cost of an index scan to the default value. + </para> + </listitem> + </varlistentry> + </variablelist> </para> - - <variablelist> - <varlistentry> - <term> - Value - </term> - <listitem> - <para> - Maximum number of rows to return for a query. The default is to allow - an unlimited number of rows. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term> - <replaceable class="parameter">#</replaceable> - </term> - <listitem> - <para> - Sets the maximum number of rows returned by a - query to <replaceable class="parameter">#</replaceable>. - </para> - </listitem> - </varlistentry> - <varlistentry> - <term> - DEFAULT - </term> - <listitem> - <para> - Sets the maximum number of rows returned by a query to be unlimited. - </para> - </listitem> - </varlistentry> - </variablelist> + <para> - By default, there is no limit to the number of rows - returned by a query. + The frontend may be initialized by setting the PGCOSTINDEX + environment variable. </para> </listitem> </varlistentry> - </variablelist> - <variablelist> <varlistentry> <term> - TRANSACTION ISOLATION LEVEL + GEQO </term> <listitem> <para> - Sets the isolation level for the current transaction. - + Sets the threshold for using the genetic optimizer algorithm. + <variablelist> <varlistentry> <term> - <replaceable class="parameter">value</replaceable> + ON </term> <listitem> <para> - Sets the isolation level for the current transaction to - 'SERIALIZABLE' or 'READ COMMITTED'. - SERIALIZABLE means that the current transaction will place a - lock on every row read, so later reads in that transaction - see the rows unmodified by other transactions. - READ COMMITTED means that the current transaction reads only - committed rows. READ COMMITTED is the default. + enables the genetic optimizer algorithm + for statements with 6 or more tables. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term> + ON=<replaceable class="parameter">#</replaceable> + </term> + <listitem> + <para> + Takes an integer argument to enable the genetic optimizer algorithm + for statements with <replaceable class="parameter">#</replaceable> + or more tables in the query. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term> + OFF + </term> + <listitem> + <para> + disables the genetic optimizer algorithm. </para> </listitem> </varlistentry> - </para> - <varlistentry> <term> DEFAULT </term> <listitem> <para> - Sets the isolation level for the current transaction to - 'READ COMMITTED'. + Equivalent to specifying <command>SET GEQO='ON'</command> </para> </listitem> </varlistentry> </variablelist> </para> - <variablelist> + <para> + This algorithm is on by default, which used GEQO for + statements of eleven or more tables. + (See the chapter on GEQO in the Programmer's Guide + for more information). + </para> + <para> + The frontend may be initialized by setting PGGEQO + environment variable. + </para> + <para> + It may be useful when joining big relations with + small ones. This algorithm is off by default. + It's not used by GEQO anyway. + </para> + </listitem> + </varlistentry> + <varlistentry> <term> - CLIENT_ENCODING | NAMES + KSQO </term> <listitem> <para> - Sets the multi-byte client encoding - + <firstterm>Key Set Query Optimizer</firstterm> forces the query optimizer + to optimize repetative OR clauses such as generated by + <productname>MicroSoft Access</productname>: + <variablelist> <varlistentry> <term> - <replaceable class="parameter">value</replaceable> + ON </term> <listitem> <para> - Sets the multi-byte client encoding. + enables this optimization. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term> + OFF + </term> + <listitem> + <para> + disables this optimization. </para> </listitem> </varlistentry> - </para> <varlistentry> <term> @@ -597,103 +584,113 @@ SET TIME ZONE { '<REPLACEABLE CLASS="PARAMETER">timezone</REPLACEABLE>' | LOCAL </term> <listitem> <para> - Sets the multi-byte client encoding. + Equivalent to specifying <command>SET KSQO='OFF'</command>. </para> </listitem> </varlistentry> </variablelist> </para> + <para> - This is only enabled if multi-byte was specified to configure. + It may be useful when joining big relations with + small ones. This algorithm is off by default. + It's not used by GEQO anyway. </para> + <para> + The frontend may be initialized by setting the PGKSQO + environment variable. + </para> + </listitem> + </varlistentry> - <variablelist> <varlistentry> <term> - SERVER_ENCODING + QUERY_LIMIT </term> <listitem> <para> - Sets the multi-byte server encoding - + Sets the maximum number of rows returned by a query. + By default, there is no limit to the number of rows + returned by a query. + <variablelist> <varlistentry> <term> - <replaceable class="parameter">value</replaceable> + <replaceable class="parameter">#</replaceable> </term> <listitem> <para> - Sets the multi-byte server encoding. + Sets the maximum number of rows returned by a + query to <replaceable class="parameter">#</replaceable>. </para> </listitem> </varlistentry> - </para> - <varlistentry> <term> DEFAULT </term> <listitem> <para> - Sets the multi-byte server encoding. + Sets the maximum number of rows returned by a query to be unlimited. </para> </listitem> </varlistentry> </variablelist> </para> - <para> - This is only enabled if multi-byte was specified to configure. - </para> - + </listitem> + </varlistentry> + </variablelist> + </para> + </refsect2> - </REFSECT2> - - <REFSECT2 ID="R2-SQL-SET-2"> - <REFSECT2INFO> - <DATE>1998-09-24</DATE> - </REFSECT2INFO> - <TITLE> + <refsect2 id="R2-SQL-SET-2"> + <refsect2info> + <date>1998-09-24</date> + </refsect2info> + <title> Outputs - </TITLE> - <PARA> + </title> + <para> - <VARIABLELIST> - <VARLISTENTRY> - <TERM> + <variablelist> + <varlistentry> + <term> <returnvalue>SET VARIABLE</returnvalue> - </TERM> - <LISTITEM> - <PARA> + </term> + <listitem> + <para> Message returned if successfully. </para> </listitem> </varlistentry> - <VARLISTENTRY> - <TERM> - <returnvalue>WARN: Bad value for <replaceable class="parameter">variable</replaceable> (<replaceable class="parameter">value</replaceable>)</returnvalue> - </TERM> - <LISTITEM> - <PARA> - If the command fails to set variable. + <varlistentry> + <term> + <returnvalue>WARN: Bad value for + <replaceable class="parameter">variable</replaceable> + (<replaceable class="parameter">value</replaceable>)</returnvalue> + </term> + <listitem> + <para> + If the command fails to set the specified variable. </para> </listitem> </varlistentry> - </VARIABLELIST> + </variablelist> </para> - </REFSECT2> - </REFSYNOPSISDIV> + </refsect2> + </refsynopsisdiv> - <REFSECT1 ID="R1-SQL-SET-1"> - <REFSECT1INFO> - <DATE>1998-09-24</DATE> - </REFSECT1INFO> - <TITLE> + <refsect1 id="R1-SQL-SET-1"> + <refsect1info> + <date>1998-09-24</date> + </refsect1info> + <title> Description - </TITLE> - <PARA> + </title> + <para> <command>SET</command> will modify configuration parameters for variable during a session. </para> @@ -707,20 +704,20 @@ SET TIME ZONE { '<REPLACEABLE CLASS="PARAMETER">timezone</REPLACEABLE>' | LOCAL <para> <command>SET TIME ZONE</command> changes the session's default time zone offset. - A SQL-session always begins with an initial default time zone + An SQL-session always begins with an initial default time zone offset. The <command>SET TIME ZONE</command> statement is used to change the default time zone offset for the current SQL session. </para> - <REFSECT2 ID="R2-SQL-SET-3"> - <REFSECT2INFO> - <DATE>1998-09-24</DATE> - </REFSECT2INFO> - <TITLE> + <refsect2 id="R2-SQL-SET-3"> + <refsect2info> + <date>1998-09-24</date> + </refsect2info> + <title> Notes - </TITLE> - <PARA> + </title> + <para> The <command>SET <replaceable class="parameter">variable</replaceable></command> statement is a <productname>Postgres</productname> language extension. </para> @@ -728,16 +725,16 @@ SET TIME ZONE { '<REPLACEABLE CLASS="PARAMETER">timezone</REPLACEABLE>' | LOCAL Refer to <command>SHOW</command> and <command>RESET</command> to display or reset the current values. </para> - </REFSECT2> - </REFSECT1> + </refsect2> + </refsect1> - <REFSECT1 ID="R1-SQL-SET-2"> - <TITLE> + <refsect1 id="R1-SQL-SET-2"> + <title> Usage - </TITLE> - <PARA> - </PARA> - <ProgramListing> + </title> + <para> + </para> + <programlisting> --Set the style of date to ISO: -- SET DATESTYLE TO 'ISO'; @@ -771,25 +768,25 @@ SET TIME ZONE { '<REPLACEABLE CLASS="PARAMETER">timezone</REPLACEABLE>' | LOCAL today ---------------------- 1998-03-31 17:41:31+02 - </ProgramListing> + </programlisting> - </REFSECT1> + </refsect1> - <REFSECT1 ID="R1-SQL-SET-3"> - <TITLE> + <refsect1 id="R1-SQL-SET-3"> + <title> Compatibility - </TITLE> - <PARA> - </PARA> + </title> + <para> + </para> - <REFSECT2 ID="R2-SQL-SET-4"> - <REFSECT2INFO> - <DATE>1998-09-24</DATE> - </REFSECT2INFO> - <TITLE> + <refsect2 id="R2-SQL-SET-4"> + <refsect2info> + <date>1998-09-24</date> + </refsect2info> + <title> SQL92 - </TITLE> - <PARA> + </title> + <para> There is no <command>SET <replaceable class="parameter">variable</replaceable></command> in <acronym>SQL92</acronym>. @@ -804,7 +801,7 @@ SET TIME ZONE { '<REPLACEABLE CLASS="PARAMETER">timezone</REPLACEABLE>' | LOCAL </para> </refsect2> </refsect1> -</REFENTRY> +</refentry> <!-- Keep this comment at the end of the file Local variables: |