Function execute

gpcontrib/orafce/dbms_sql.c:916–1316

}

static uint64
execute(CursorData *c)
{
	last_row_count = 0;

	/* clean space with saved result */
	if (!c->cursor_xact_cxt)
	{
		MemoryContextCallback *mcb;
		MemoryContext oldcxt;

		c->cursor_xact_cxt = AllocSetContextCreate(TopTransactionContext,
												   "dbms_sql transaction context",
												   ALLOCSET_DEFAULT_SIZES);

		oldcxt = MemoryContextSwitchTo(c->cursor_xact_cxt);
		mcb = palloc0(sizeof(MemoryContextCallback));

		mcb->func = cursor_xact_cxt_deletion_callback;
		mcb->arg = c;

		MemoryContextRegisterResetCallback(c->cursor_xact_cxt, mcb);

		MemoryContextSwitchTo(oldcxt);
	}
	else
	{
		MemoryContext	save_cxt = c->cursor_xact_cxt;

		MemoryContextReset(c->cursor_xact_cxt);
		c->cursor_xact_cxt = save_cxt;

		c->casts = NULL;
		c->tupdesc = NULL;
		c->tuples_cxt = NULL;
	}

	c->result_cxt = AllocSetContextCreate(c->cursor_xact_cxt,
										  "dbms_sql short life context",
										  ALLOCSET_DEFAULT_SIZES);

	/*
	 * When column definitions are available, build final query
	 * and open cursor for fetching. When column definitions are
	 * missing, then the statement can be called with high frequency
	 * etc INSERT, UPDATE, so use cached plan.
	 */
	if (c->columns)
	{
		Datum	   *values;
		Oid		   *types;
		char	   *nulls;
		ListCell   *lc;
		int			i;
		MemoryContext oldcxt;
		uint64		batch_rows = 0;

		oldcxt = MemoryContextSwitchTo(c->cursor_xact_cxt);