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SPI_cursor_open_with_args
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SPI_cursor_open_with_args

SPI_cursor_open_with_args — set up a cursor using a query and parameters

Synopsis

Portal SPI_cursor_open_with_args(const char *name,
                                 const char *command,
                                 int nargs, Oid *argtypes,
                                 Datum *values, const char *nulls,
                                 bool read_only, int cursorOptions)

Description

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.

Arguments

`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 + Ifnulls 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

Return Value

Pointer to portal containing the cursor. Note there is no error return convention; any error will be reported via elog.

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