SPI_cursor_open_with_args — set up a cursor using a query and parameters
Portal SPI_cursor_open_with_args(const char *name
, const char *command
, intnargs
, Oid *argtypes
, Datum *values
, const char *nulls
, boolread_only
, intcursorOptions
)
SPI_cursor_open_with_args
sets up a cursor
(internally, a portal) that will execute the specified query.
Most of the parameters have the same meanings as the corresponding
parameters to SPI_prepare_cursor
and SPI_cursor_open
.
For one-time query execution, this function should be preferred
over SPI_prepare_cursor
followed by
SPI_cursor_open
.
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.
The passed-in parameter data will be copied into the cursor's portal, so it can be freed while the cursor still exists.
const char * name
name for portal, or NULL
to let the system
select a name
const char * command
command string
int nargs
number of input parameters ($1
, $2
, etc.)
Oid * argtypes
an array of length nargs
, containing the
OIDs of the data types of the parameters
Datum * values
an array of length nargs
, containing the actual
parameter values
const char * nulls
an array of length nargs
, describing which
parameters are null
If nulls
is NULL
then
SPI_cursor_open_with_args
assumes that no parameters
are null. Otherwise, each entry of the nulls
array should be ' '
if the corresponding parameter
value is non-null, or 'n'
if the corresponding parameter
value is null. (In the latter case, the actual value in the
corresponding values
entry doesn't matter.) Note
that nulls
is not a text string, just an array:
it does not need a '\0'
terminator.
bool read_only
true
for read-only execution
int cursorOptions
integer bit mask of cursor options; zero produces default behavior
Pointer to portal containing the cursor. Note there is no error
return convention; any error will be reported via elog
.