Function ExecInitTidRangeScan

src/backend/executor/nodeTidrangescan.c:354–413

---------------------------------------------------------------- * ExecInitTidRangeScan * * Initializes the tid range scan's state information, creates * scan keys, and opens the scan relation. * * Parameters: * node: TidRangeScan node produced by the planner. * estate: the execution state initialized in InitPlan. * ---------------------------------------------------------------

 * ----------------------------------------------------------------
 */
TidRangeScanState *
ExecInitTidRangeScan(TidRangeScan *node, EState *estate, int eflags)
{
	TidRangeScanState *tidrangestate;
	Relation	currentRelation;

	/*
	 * create state structure
	 */
	tidrangestate = makeNode(TidRangeScanState);
	tidrangestate->ss.ps.plan = (Plan *) node;
	tidrangestate->ss.ps.state = estate;
	tidrangestate->ss.ps.ExecProcNode = ExecTidRangeScan;

	/*
	 * Miscellaneous initialization
	 *
	 * create expression context for node
	 */
	ExecAssignExprContext(estate, &tidrangestate->ss.ps);

	/*
	 * mark scan as not in progress, and TID range as not computed yet
	 */
	tidrangestate->trss_inScan = false;

	/*
	 * open the scan relation
	 */
	currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid, eflags);

	tidrangestate->ss.ss_currentRelation = currentRelation;
	tidrangestate->ss.ss_currentScanDesc = NULL;	/* no table scan here */

	/*
	 * get the scan type from the relation descriptor.
	 */
	ExecInitScanTupleSlot(estate, &tidrangestate->ss,
						  RelationGetDescr(currentRelation),
						  table_slot_callbacks(currentRelation));

	/*
	 * Initialize result type and projection.
	 */
	ExecInitResultTypeTL(&tidrangestate->ss.ps);
	ExecAssignScanProjectionInfo(&tidrangestate->ss);

	/*
	 * initialize child expressions
	 */
	tidrangestate->ss.ps.qual =
		ExecInitQual(node->scan.plan.qual, (PlanState *) tidrangestate);

	TidExprListCreate(tidrangestate);

	/*
	 * all done.
	 */