'\" t
.\"     Title: SPI_returntuple
.\"    Author: The PostgreSQL Global Development Group
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: 2018
.\"    Manual: PostgreSQL 10.4 Documentation
.\"    Source: PostgreSQL 10.4
.\"  Language: English
.\"
.TH "SPI_RETURNTUPLE" "3" "2018" "PostgreSQL 10.4" "PostgreSQL 10.4 Documentation"
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.SH "NAME"
SPI_returntuple \- prepare to return a tuple as a Datum
.SH "SYNOPSIS"
.sp
.nf
HeapTupleHeader SPI_returntuple(HeapTuple \fIrow\fR, TupleDesc \fIrowdesc\fR)
.fi
.SH "DESCRIPTION"
.PP
\fBSPI_returntuple\fR
makes a copy of a row in the upper executor context, returning it in the form of a row type
Datum\&. The returned pointer need only be converted to
Datum
via
\fBPointerGetDatum\fR
before returning\&.
.PP
This function can only be used while connected to SPI\&. Otherwise, it returns NULL and sets
\fISPI_result\fR
to
SPI_ERROR_UNCONNECTED\&.
.PP
Note that this should be used for functions that are declared to return composite types\&. It is not used for triggers; use
\fBSPI_copytuple\fR
for returning a modified row in a trigger\&.
.SH "ARGUMENTS"
.PP
HeapTuple \fIrow\fR
.RS 4
row to be copied
.RE
.PP
TupleDesc \fIrowdesc\fR
.RS 4
descriptor for row (pass the same descriptor each time for most effective caching)
.RE
.SH "RETURN VALUE"
.PP
HeapTupleHeader
pointing to copied row, or
NULL
on error (see
\fISPI_result\fR
for an error indication)