diff options
| -rw-r--r-- | doc/src/sgml/plperl.sgml | 21 | ||||
| -rw-r--r-- | doc/src/sgml/plpython.sgml | 13 | ||||
| -rw-r--r-- | doc/src/sgml/pltcl.sgml | 8 |
3 files changed, 32 insertions, 10 deletions
diff --git a/doc/src/sgml/plperl.sgml b/doc/src/sgml/plperl.sgml index 6c81ee8fbe1..25b1077ad73 100644 --- a/doc/src/sgml/plperl.sgml +++ b/doc/src/sgml/plperl.sgml @@ -441,7 +441,7 @@ use strict; <variablelist> <varlistentry> <term> - <literal><function>spi_exec_query</function>(<replaceable>query</replaceable> [, <replaceable>max-rows</replaceable>])</literal> + <literal><function>spi_exec_query</function>(<replaceable>query</replaceable> [, <replaceable>limit</replaceable>])</literal> <indexterm> <primary>spi_exec_query</primary> <secondary>in PL/Perl</secondary> @@ -449,9 +449,17 @@ use strict; </term> <listitem> <para> - <literal>spi_exec_query</literal> executes an SQL command and -returns the entire row set as a reference to an array of hash -references. <emphasis>You should only use this command when you know + <function>spi_exec_query</function> executes an SQL command and +returns the entire row set as a reference to an array of hash references. +If <replaceable>limit</replaceable> is specified and is greater than zero, +then <function>spi_exec_query</function> retrieves at +most <replaceable>limit</replaceable> rows, much as if the query included +a <literal>LIMIT</literal> clause. Omitting <replaceable>limit</replaceable> +or specifying it as zero results in no row limit. + </para> + + <para> +<emphasis>You should only use this command when you know that the result set will be relatively small.</emphasis> Here is an example of a query (<command>SELECT</command> command) with the optional maximum number of rows: @@ -643,7 +651,10 @@ $plan = spi_prepare('SELECT * FROM test WHERE id > $1 AND name = $2', by <literal>spi_exec_query</literal>, or in <literal>spi_query_prepared</literal> which returns a cursor exactly as <literal>spi_query</literal> does, which can be later passed to <literal>spi_fetchrow</literal>. The optional second parameter to <literal>spi_exec_prepared</literal> is a hash reference of attributes; - the only attribute currently supported is <literal>limit</literal>, which sets the maximum number of rows returned by a query. + the only attribute currently supported is <literal>limit</literal>, which + sets the maximum number of rows returned from the query. + Omitting <literal>limit</literal> or specifying it as zero results in no + row limit. </para> <para> diff --git a/doc/src/sgml/plpython.sgml b/doc/src/sgml/plpython.sgml index e190c90f453..e05e607aba0 100644 --- a/doc/src/sgml/plpython.sgml +++ b/doc/src/sgml/plpython.sgml @@ -789,7 +789,7 @@ $$ LANGUAGE plpython3u; <variablelist> <varlistentry> - <term><literal>plpy.<function>execute</function>(<replaceable>query</replaceable> [, <replaceable>max-rows</replaceable>])</literal></term> + <term><literal>plpy.<function>execute</function>(<replaceable>query</replaceable> [, <replaceable>limit</replaceable>])</literal></term> <listitem> <para> Calling <function>plpy.execute</function> with a query string and an @@ -798,6 +798,15 @@ $$ LANGUAGE plpython3u; </para> <para> + If <replaceable>limit</replaceable> is specified and is greater than + zero, then <function>plpy.execute</function> retrieves at + most <replaceable>limit</replaceable> rows, much as if the query + included a <literal>LIMIT</literal> + clause. Omitting <replaceable>limit</replaceable> or specifying it as + zero results in no row limit. + </para> + + <para> The result object emulates a list or dictionary object. The result object can be accessed by row number and column name. For example: <programlisting> @@ -887,7 +896,7 @@ foo = rv[i]["my_column"] <varlistentry> <term><literal>plpy.<function>prepare</function>(<replaceable>query</replaceable> [, <replaceable>argtypes</replaceable>])</literal></term> - <term><literal>plpy.<function>execute</function>(<replaceable>plan</replaceable> [, <replaceable>arguments</replaceable> [, <replaceable>max-rows</replaceable>]])</literal></term> + <term><literal>plpy.<function>execute</function>(<replaceable>plan</replaceable> [, <replaceable>arguments</replaceable> [, <replaceable>limit</replaceable>]])</literal></term> <listitem> <para> <indexterm><primary>preparing a query</primary><secondary>in PL/Python</secondary></indexterm> diff --git a/doc/src/sgml/pltcl.sgml b/doc/src/sgml/pltcl.sgml index bf56ba6b1c6..b31f2c1330f 100644 --- a/doc/src/sgml/pltcl.sgml +++ b/doc/src/sgml/pltcl.sgml @@ -341,9 +341,11 @@ $$ LANGUAGE pltcl; </para> <para> The optional <literal>-count</literal> value tells - <function>spi_exec</function> the maximum number of rows - to process in the command. The effect of this is comparable to - setting up a query as a cursor and then saying <literal>FETCH <replaceable>n</replaceable></literal>. + <function>spi_exec</function> to stop + once <replaceable>n</replaceable> rows have been retrieved, + much as if the query included a <literal>LIMIT</literal> clause. + If <replaceable>n</replaceable> is zero, the query is run to + completion, the same as when <literal>-count</literal> is omitted. </para> <para> If the command is a <command>SELECT</command> statement, the values of the |