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'\" t
.\"     Title: SPI_cursor_parse_open
.\"    Author: The PostgreSQL Global Development Group
.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
.\"      Date: 2024
.\"    Manual: PostgreSQL 15.6 Documentation
.\"    Source: PostgreSQL 15.6
.\"  Language: English
.\"
.TH "SPI_CURSOR_PARSE_OPEN" "3" "2024" "PostgreSQL 15.6" "PostgreSQL 15.6 Documentation"
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.SH "NAME"
SPI_cursor_parse_open \- set up a cursor using a query string and parameters
.SH "SYNOPSIS"
.sp
.nf
Portal SPI_cursor_parse_open(const char *\fIname\fR,
                             const char *\fIcommand\fR,
                             const SPIParseOpenOptions * \fIoptions\fR)
.fi
.SH "DESCRIPTION"
.PP
\fBSPI_cursor_parse_open\fR
sets up a cursor (internally, a portal) that will execute the specified query string\&. This is comparable to
\fBSPI_prepare_cursor\fR
followed by
\fBSPI_cursor_open_with_paramlist\fR, except that parameter references within the query string are handled entirely by supplying a
ParamListInfo
object\&.
.PP
For one\-time query execution, this function should be preferred over
\fBSPI_prepare_cursor\fR
followed by
\fBSPI_cursor_open_with_paramlist\fR\&. If the same command is to be executed with many different parameters, either method might be faster, depending on the cost of re\-planning versus the benefit of custom plans\&.
.PP
The
\fIoptions\->params\fR
object should normally mark each parameter with the
PARAM_FLAG_CONST
flag, since a one\-shot plan is always used for the query\&.
.PP
The passed\-in parameter data will be copied into the cursor\*(Aqs portal, so it can be freed while the cursor still exists\&.
.SH "ARGUMENTS"
.PP
const char * \fIname\fR
.RS 4
name for portal, or
NULL
to let the system select a name
.RE
.PP
const char * \fIcommand\fR
.RS 4
command string
.RE
.PP
const SPIParseOpenOptions * \fIoptions\fR
.RS 4
struct containing optional arguments
.RE
.PP
Callers should always zero out the entire
\fIoptions\fR
struct, then fill whichever fields they want to set\&. This ensures forward compatibility of code, since any fields that are added to the struct in future will be defined to behave backwards\-compatibly if they are zero\&. The currently available
\fIoptions\fR
fields are:
.PP
ParamListInfo \fIparams\fR
.RS 4
data structure containing query parameter types and values; NULL if none
.RE
.PP
int \fIcursorOptions\fR
.RS 4
integer bit mask of cursor options; zero produces default behavior
.RE
.PP
bool \fIread_only\fR
.RS 4
true
for read\-only execution
.RE
.SH "RETURN VALUE"
.PP
Pointer to portal containing the cursor\&. Note there is no error return convention; any error will be reported via
\fBelog\fR\&.