<!--
-$PostgreSQL: pgsql/doc/src/sgml/spi.sgml,v 1.30 2003/12/01 22:07:57 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/spi.sgml,v 1.31 2004/03/05 00:47:01 momjian Exp $
-->
<chapter id="spi">
<!-- *********************************************** -->
+<refentry id="spi-spi-getargcount">
+ <refmeta>
+ <refentrytitle>SPI_getargcount</refentrytitle>
+ </refmeta>
+
+ <refnamediv>
+ <refname>SPI_getargcount</refname>
+ <refpurpose>returns the number of arguments needed when executing a plan
+ prepared by <function>SPI_prepare</function></refpurpose>
+ </refnamediv>
+
+ <indexterm><primary>SPI_getargcount</primary></indexterm>
+
+ <refsynopsisdiv>
+<synopsis>
+int SPI_getargcount(void * <parameter>plan</parameter>)
+</synopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para>
+ <function>SPI_getargcount</function> returns the number of arguments needed
+ when executing a plan prepared by <function>SPI_prepare</function>.
+ </para>
+ </refsect1>
+
+ <refsect1>
+ <title>Arguments</title>
+
+ <variablelist>
+ <varlistentry>
+ <term><literal>void * <parameter>plan</parameter></literal></term>
+ <listitem>
+ <para>
+ execution plan (returned by <function>SPI_prepare</function>)
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+ <para>
+ The expected argument count for the <parameter>plan</parameter> or
+ <symbol>SPI_ERROR_ARGUMENT</symbol> if the <parameter>plan
+ </parameter> is <symbol>NULL</symbol>
+ </para>
+ </refsect1>
+</refentry>
+
+<!-- *********************************************** -->
+
+<refentry id="spi-spi-getargtypeid">
+ <refmeta>
+ <refentrytitle>SPI_getargtypeid</refentrytitle>
+ </refmeta>
+
+ <refnamediv>
+ <refname>SPI_getargtypeid</refname>
+ <refpurpose>returns the expected typeid for the specified argument when
+ executing a plan prepared by <function>SPI_prepare</function></refpurpose>
+ </refnamediv>
+
+ <indexterm><primary>SPI_getargtypeid</primary></indexterm>
+
+ <refsynopsisdiv>
+<synopsis>
+Oid SPI_getargtypeid(void * <parameter>plan</parameter>, int <parameter>argIndex</parameter>)
+</synopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para>
+ <function>SPI_getargtypeid</function> returns the Oid representing the type
+ id for argument at <parameter>argIndex</parameter> in a plan prepared by
+ <function>SPI_prepare</function>. First argument is at index zero.
+ </para>
+ </refsect1>
+
+ <refsect1>
+ <title>Arguments</title>
+
+ <variablelist>
+ <varlistentry>
+ <term><literal>void * <parameter>plan</parameter></literal></term>
+ <listitem>
+ <para>
+ execution plan (returned by <function>SPI_prepare</function>)
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><literal>int <parameter>argIndex</parameter></literal></term>
+ <listitem>
+ <para>
+ zero based index of the argument
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+ <para>
+ The type id of the argument at the given index or <symbol>
+ SPI_ERROR_ARGUMENT</symbol> if the <parameter>plan</parameter> is
+ <symbol>NULL</symbol> or <parameter>argIndex</parameter> is less than 0 or
+ not less than the number of arguments declared for the <parameter>plan
+ </parameter>
+ </para>
+ </refsect1>
+</refentry>
+
+<!-- *********************************************** -->
+
+<refentry id="spi-spi-is_cursor_plan">
+ <refmeta>
+ <refentrytitle>SPI_is_cursor_plan</refentrytitle>
+ </refmeta>
+
+ <refnamediv>
+ <refname>SPI_is_cursor_plan</refname>
+ <refpurpose>returns <symbol>true</symbol> if a plan
+ prepared by <function>SPI_prepare</function> can be passed
+ as an argument to <function>SPI_cursor_open</function></refpurpose>
+ </refnamediv>
+
+ <indexterm><primary>SPI_is_cursor_plan</primary></indexterm>
+
+ <refsynopsisdiv>
+<synopsis>
+bool SPI_is_cursor_plan(void * <parameter>plan</parameter>)
+</synopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para>
+ <function>SPI_is_cursor_plan</function> returns <symbol>true</symbol>
+ if a plan prepared by <function>SPI_prepare</function> can be passed
+ as an argument to <function>SPI_cursor_open</function> and <symbol>
+ false</symbol> if that is not the case. The criteria is that the
+ <parameter>plan</parameter> represents one single command and that this
+ command is a <command>SELECT</command> without an <command>INTO</command>
+ clause.
+ </para>
+ </refsect1>
+
+ <refsect1>
+ <title>Arguments</title>
+
+ <variablelist>
+ <varlistentry>
+ <term><literal>void * <parameter>plan</parameter></literal></term>
+ <listitem>
+ <para>
+ execution plan (returned by <function>SPI_prepare</function>)
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+ <para>
+ <symbol>true</symbol> or <symbol>false</symbol> to indicate if the
+ <parameter>plan</parameter> can produce a cursor or not, or
+ <symbol>SPI_ERROR_ARGUMENT</symbol> if the <parameter>plan</parameter>
+ is <symbol>NULL</symbol>
+ </para>
+ </refsect1>
+</refentry>
+
+<!-- *********************************************** -->
+
<refentry id="spi-spi-execp">
<refmeta>
<refentrytitle>SPI_execp</refentrytitle>
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/executor/spi.c,v 1.109 2003/12/02 19:26:47 joe Exp $
+ * $PostgreSQL: pgsql/src/backend/executor/spi.c,v 1.110 2004/03/05 00:47:01 momjian Exp $
*
*-------------------------------------------------------------------------
*/
PortalDrop(portal, false);
}
+/*
+ * Returns the Oid representing the type id for argument at argIndex. First
+ * parameter is at index zero.
+ */
+Oid
+SPI_getargtypeid(void *plan, int argIndex)
+{
+ if (plan == NULL || argIndex < 0 || argIndex >= ((_SPI_plan*)plan)->nargs)
+ {
+ SPI_result = SPI_ERROR_ARGUMENT;
+ return InvalidOid;
+ }
+ return ((_SPI_plan *) plan)->argtypes[argIndex];
+}
+
+/*
+ * Returns the number of arguments for the prepared plan.
+ */
+int
+SPI_getargcount(void *plan)
+{
+ if (plan == NULL)
+ {
+ SPI_result = SPI_ERROR_ARGUMENT;
+ return -1;
+ }
+ return ((_SPI_plan *) plan)->nargs;
+}
+
+/*
+ * Returns true if the plan contains exactly one command
+ * and that command originates from normal SELECT (i.e.
+ * *not* a SELECT ... INTO). In essence, the result indicates
+ * if the command can be used with SPI_cursor_open
+ *
+ * Parameters
+ * plan A plan previously prepared using SPI_prepare
+ */
+bool
+SPI_is_cursor_plan(void *plan)
+{
+ List *qtlist;
+ _SPI_plan *spiplan = (_SPI_plan *) plan;
+ if (spiplan == NULL)
+ {
+ SPI_result = SPI_ERROR_ARGUMENT;
+ return false;
+ }
+
+ qtlist = spiplan->qtlist;
+ if(length(spiplan->ptlist) == 1 && length(qtlist) == 1)
+ {
+ Query *queryTree = (Query *) lfirst((List *) lfirst(qtlist));
+ if(queryTree->commandType == CMD_SELECT && queryTree->into == NULL)
+ return true;
+ }
+ return false;
+}
+
/* =================== private functions =================== */
/*