/*
* ExecAssignScanProjectionInfoWithVarno
* As above, but caller can specify varno expected in Vars in the tlist.
*/
void
ExecAssignScanProjectionInfoWithVarno(ScanState *node, Index varno)
{
TupleDesc tupdesc = node->ss_ScanTupleSlot->tts_tupleDescriptor;
ExecConditionalAssignProjectionInfo(&node->ps, tupdesc, varno);
}
/*
* ExecAssignScanProjectionInfo
* Set up projection info for a scan node, if necessary.
*
* We can avoid a projection step if the requested tlist exactly matches
* the underlying tuple type. If so, we just set ps_ProjInfo to NULL.
* Note that this case occurs not only for simple "SELECT * FROM ...", but
* also in most cases where there are joins or other processing nodes above
* the scan node, because the planner will preferentially generate a matching
* tlist.
*
* ExecAssignScanType must have been called already.
*/
void
ExecAssignScanProjectionInfo(ScanState *node)
{
Scan *scan = (Scan *) node->ps.plan;
TupleDesc tupdesc = node->ss_ScanTupleSlot->tts_tupleDescriptor;
ExecConditionalAssignProjectionInfo(&node->ps, tupdesc, scan->scanrelid);
}
/* ----------------------------------------------------------------
* ExecInitGather
* ----------------------------------------------------------------
*/
GatherMergeState *
ExecInitGatherMerge(GatherMerge *node, EState *estate, int eflags)
{
GatherMergeState *gm_state;
Plan *outerNode;
TupleDesc tupDesc;
/* Gather merge node doesn't have innerPlan node. */
Assert(innerPlan(node) == NULL);
/*
* create state structure
*/
gm_state = makeNode(GatherMergeState);
gm_state->ps.plan = (Plan *) node;
gm_state->ps.state = estate;
gm_state->ps.ExecProcNode = ExecGatherMerge;
gm_state->initialized = false;
gm_state->gm_initialized = false;
gm_state->tuples_needed = -1;
/*
* Miscellaneous initialization
*
* create expression context for node
*/
ExecAssignExprContext(estate, &gm_state->ps);
/*
* GatherMerge doesn't support checking a qual (it's always more efficient
* to do it in the child node).
*/
Assert(!node->plan.qual);
/*
* now initialize outer plan
*/
outerNode = outerPlan(node);
outerPlanState(gm_state) = ExecInitNode(outerNode, estate, eflags);
/*
* Leader may access ExecProcNode result directly (if
* need_to_scan_locally), or from workers via tuple queue. So we can't
* trivially rely on the slot type being fixed for expressions evaluated
* within this node.
*/
gm_state->ps.outeropsset = true;
gm_state->ps.outeropsfixed = false;
/*
* Store the tuple descriptor into gather merge state, so we can use it
* while initializing the gather merge slots.
*/
tupDesc = ExecGetResultType(outerPlanState(gm_state));
gm_state->tupDesc = tupDesc;
/*
* Initialize result type and projection.
*/
ExecInitResultTypeTL(&gm_state->ps);
ExecConditionalAssignProjectionInfo(&gm_state->ps, tupDesc, OUTER_VAR);
/*
* Without projections result slot type is not trivially known, see
* comment above.
*/
if (gm_state->ps.ps_ProjInfo == NULL)
{
gm_state->ps.resultopsset = true;
gm_state->ps.resultopsfixed = false;
}
/*
* initialize sort-key information
*/
if (node->numCols)
{
int i;
gm_state->gm_nkeys = node->numCols;
gm_state->gm_sortkeys =
palloc0(sizeof(SortSupportData) * node->numCols);
for (i = 0; i < node->numCols; i++)
{
SortSupport sortKey = gm_state->gm_sortkeys + i;
sortKey->ssup_cxt = CurrentMemoryContext;
sortKey->ssup_collation = node->collations[i];
sortKey->ssup_nulls_first = node->nullsFirst[i];
sortKey->ssup_attno = node->sortColIdx[i];
/*
* We don't perform abbreviated key conversion here, for the same
* reasons that it isn't used in MergeAppend
*/
sortKey->abbreviate = false;
PrepareSortSupportFromOrderingOp(node->sortOperators[i], sortKey);
}
}
/* Now allocate the workspace for gather merge */
gather_merge_setup(gm_state);
return gm_state;
}
/* ----------------------------------------------------------------
* ExecInitGather
* ----------------------------------------------------------------
*/
GatherState *
ExecInitGather(Gather *node, EState *estate, int eflags)
{
GatherState *gatherstate;
Plan *outerNode;
bool hasoid;
TupleDesc tupDesc;
/* Gather node doesn't have innerPlan node. */
Assert(innerPlan(node) == NULL);
/*
* create state structure
*/
gatherstate = makeNode(GatherState);
gatherstate->ps.plan = (Plan *) node;
gatherstate->ps.state = estate;
gatherstate->ps.ExecProcNode = ExecGather;
gatherstate->initialized = false;
gatherstate->need_to_scan_locally =
!node->single_copy && parallel_leader_participation;
gatherstate->tuples_needed = -1;
/*
* Miscellaneous initialization
*
* create expression context for node
*/
ExecAssignExprContext(estate, &gatherstate->ps);
/*
* Gather doesn't support checking a qual (it's always more efficient to
* do it in the child node).
*/
Assert(!node->plan.qual);
/*
* tuple table initialization
*/
gatherstate->funnel_slot = ExecInitExtraTupleSlot(estate);
ExecInitResultTupleSlot(estate, &gatherstate->ps);
/*
* now initialize outer plan
*/
outerNode = outerPlan(node);
outerPlanState(gatherstate) = ExecInitNode(outerNode, estate, eflags);
/*
* Initialize funnel slot to same tuple descriptor as outer plan.
*/
if (!ExecContextForcesOids(outerPlanState(gatherstate), &hasoid))
hasoid = false;
tupDesc = ExecTypeFromTL(outerNode->targetlist, hasoid);
ExecSetSlotDescriptor(gatherstate->funnel_slot, tupDesc);
/*
* Initialize result tuple type and projection info.
*/
ExecAssignResultTypeFromTL(&gatherstate->ps);
ExecConditionalAssignProjectionInfo(&gatherstate->ps, tupDesc, OUTER_VAR);
return gatherstate;
}
