spi_cursor_open

SPI_cursor_open()      PostgreSQL 7.4.19 Documentation	    SPI_cursor_open()



NAME
       SPI_cursor_open	-  set up a cursor using a plan created with SPI_pre-
       pare


SYNOPSIS
       Portal SPI_cursor_open(const char * name, void * plan, Datum * values, const char * nulls)


DESCRIPTION
       SPI_cursor_open sets up a cursor (internally, a portal) that will exe-
       cute a plan prepared by SPI_prepare.

       Using  a	 cursor	 instead of executing the plan directly has two bene-
       fits. First, the result rows can be retrieved a few at a time,  avoid-
       ing memory overrun for queries that return many rows. Second, a portal
       can outlive the current procedure (it can, in fact, live to the end of
       the current transaction). Returning the portal name to the procedure’s
       caller provides a way of returning a row set as result.

ARGUMENTS
       const char * name
	      name for portal, or NULL to let the system select a name

       void * plan
	      execution plan (returned by SPI_prepare)

       Datum * values
	      actual parameter values

       const char *nulls
	      An array describing which parameters are null values.  n	indi-
	      cates  a	null value (entry in values will be ignored); a space
	      indicates a nonnull value (entry in values is valid). If	nulls
	      is  NULL	then  SPI_cursor_open  assumes that no parameters are
	      null.

RETURN VALUE
       pointer to portal containing the cursor, or NULL on error



				  2008-01-03		    SPI_cursor_open()