Function ExecHashTableExplainInit

src/backend/executor/nodeHash.c:2547–2571

* ExecHashTableExplainInit * Called after ExecHashTableCreate to set up EXPLAIN ANALYZE reporting. */

 *      Called after ExecHashTableCreate to set up EXPLAIN ANALYZE reporting.
 */
void
ExecHashTableExplainInit(HashState *hashState, HashJoinState *hjstate,
						 HashJoinTable hashtable)
{
	MemoryContext oldcxt;
	int			nbatch = Max(hashtable->nbatch, 1);

    /* Switch to a memory context that survives until ExecutorEnd. */
    oldcxt = MemoryContextSwitchTo(hjstate->js.ps.state->es_query_cxt);

    /* Request a callback at end of query. */
    hjstate->js.ps.cdbexplainfun = ExecHashTableExplainEnd;

    /* Create workarea and attach it to the HashJoinTable. */
    hashtable->stats = (HashJoinTableStats *)palloc0(sizeof(*hashtable->stats));
    hashtable->stats->endedbatch = -1;

    /* Create per-batch statistics array. */
    hashtable->stats->batchstats =
        (HashJoinBatchStats *)palloc0(nbatch * sizeof(hashtable->stats->batchstats[0]));
    hashtable->stats->nbatchstats = nbatch;

    /* Restore caller's memory context. */
    MemoryContextSwitchTo(oldcxt);
}                               /* ExecHashTableExplainInit */


/*