1 /*-------------------------------------------------------------------------
4 * definitions for executor state nodes
7 * Portions Copyright (c) 1996-2011, PostgreSQL Global Development Group
8 * Portions Copyright (c) 1994, Regents of the University of California
10 * src/include/nodes/execnodes.h
12 *-------------------------------------------------------------------------
17 #include "access/genam.h"
18 #include "access/heapam.h"
19 #include "access/skey.h"
20 #include "nodes/params.h"
21 #include "nodes/plannodes.h"
22 #include "nodes/tidbitmap.h"
23 #include "utils/hsearch.h"
24 #include "utils/rel.h"
25 #include "utils/snapshot.h"
26 #include "utils/tuplestore.h"
30 * IndexInfo information
32 * this struct holds the information needed to construct new index
33 * entries for a particular index. Used for both index_build and
34 * retail creation of index entries.
36 * NumIndexAttrs number of columns in this index
37 * KeyAttrNumbers underlying-rel attribute numbers used as keys
38 * (zeroes indicate expressions)
39 * Expressions expr trees for expression entries, or NIL if none
40 * ExpressionsState exec state for expressions, or NIL if none
41 * Predicate partial-index predicate, or NIL if none
42 * PredicateState exec state for predicate, or NIL if none
43 * ExclusionOps Per-column exclusion operators, or NULL if none
44 * ExclusionProcs Underlying function OIDs for ExclusionOps
45 * ExclusionStrats Opclass strategy numbers for ExclusionOps
46 * Unique is it a unique index?
47 * ReadyForInserts is it valid for inserts?
48 * Concurrent are we doing a concurrent index build?
49 * BrokenHotChain did we detect any broken HOT chains?
51 * ii_Concurrent and ii_BrokenHotChain are used only during index build;
52 * they're conventionally set to false otherwise.
55 typedef struct IndexInfo
59 AttrNumber ii_KeyAttrNumbers[INDEX_MAX_KEYS];
60 List *ii_Expressions; /* list of Expr */
61 List *ii_ExpressionsState; /* list of ExprState */
62 List *ii_Predicate; /* list of Expr */
63 List *ii_PredicateState; /* list of ExprState */
64 Oid *ii_ExclusionOps; /* array with one entry per column */
65 Oid *ii_ExclusionProcs; /* array with one entry per column */
66 uint16 *ii_ExclusionStrats; /* array with one entry per column */
68 bool ii_ReadyForInserts;
70 bool ii_BrokenHotChain;
76 * List of callbacks to be called at ExprContext shutdown.
79 typedef void (*ExprContextCallbackFunction) (Datum arg);
81 typedef struct ExprContext_CB
83 struct ExprContext_CB *next;
84 ExprContextCallbackFunction function;
91 * This class holds the "current context" information
92 * needed to evaluate expressions for doing tuple qualifications
93 * and tuple projections. For example, if an expression refers
94 * to an attribute in the current inner tuple then we need to know
95 * what the current inner tuple is and so we look at the expression
98 * There are two memory contexts associated with an ExprContext:
99 * * ecxt_per_query_memory is a query-lifespan context, typically the same
100 * context the ExprContext node itself is allocated in. This context
101 * can be used for purposes such as storing function call cache info.
102 * * ecxt_per_tuple_memory is a short-term context for expression results.
103 * As the name suggests, it will typically be reset once per tuple,
104 * before we begin to evaluate expressions for that tuple. Each
105 * ExprContext normally has its very own per-tuple memory context.
107 * CurrentMemoryContext should be set to ecxt_per_tuple_memory before
108 * calling ExecEvalExpr() --- see ExecEvalExprSwitchContext().
111 typedef struct ExprContext
115 /* Tuples that Var nodes in expression may refer to */
116 TupleTableSlot *ecxt_scantuple;
117 TupleTableSlot *ecxt_innertuple;
118 TupleTableSlot *ecxt_outertuple;
120 /* Memory contexts for expression evaluation --- see notes above */
121 MemoryContext ecxt_per_query_memory;
122 MemoryContext ecxt_per_tuple_memory;
124 /* Values to substitute for Param nodes in expression */
125 ParamExecData *ecxt_param_exec_vals; /* for PARAM_EXEC params */
126 ParamListInfo ecxt_param_list_info; /* for other param types */
129 * Values to substitute for Aggref nodes in the expressions of an Agg
130 * node, or for WindowFunc nodes within a WindowAgg node.
132 Datum *ecxt_aggvalues; /* precomputed values for aggs/windowfuncs */
133 bool *ecxt_aggnulls; /* null flags for aggs/windowfuncs */
135 /* Value to substitute for CaseTestExpr nodes in expression */
136 Datum caseValue_datum;
137 bool caseValue_isNull;
139 /* Value to substitute for CoerceToDomainValue nodes in expression */
140 Datum domainValue_datum;
141 bool domainValue_isNull;
143 /* Link to containing EState (NULL if a standalone ExprContext) */
144 struct EState *ecxt_estate;
146 /* Functions to call back when ExprContext is shut down */
147 ExprContext_CB *ecxt_callbacks;
151 * Set-result status returned by ExecEvalExpr()
155 ExprSingleResult, /* expression does not return a set */
156 ExprMultipleResult, /* this result is an element of a set */
157 ExprEndResult /* there are no more elements in the set */
161 * Return modes for functions returning sets. Note values must be chosen
162 * as separate bits so that a bitmask can be formed to indicate supported
163 * modes. SFRM_Materialize_Random and SFRM_Materialize_Preferred are
164 * auxiliary flags about SFRM_Materialize mode, rather than separate modes.
168 SFRM_ValuePerCall = 0x01, /* one value returned per call */
169 SFRM_Materialize = 0x02, /* result set instantiated in Tuplestore */
170 SFRM_Materialize_Random = 0x04, /* Tuplestore needs randomAccess */
171 SFRM_Materialize_Preferred = 0x08 /* caller prefers Tuplestore */
172 } SetFunctionReturnMode;
175 * When calling a function that might return a set (multiple rows),
176 * a node of this type is passed as fcinfo->resultinfo to allow
177 * return status to be passed back. A function returning set should
178 * raise an error if no such resultinfo is provided.
180 typedef struct ReturnSetInfo
183 /* values set by caller: */
184 ExprContext *econtext; /* context function is being called in */
185 TupleDesc expectedDesc; /* tuple descriptor expected by caller */
186 int allowedModes; /* bitmask: return modes caller can handle */
187 /* result status from function (but pre-initialized by caller): */
188 SetFunctionReturnMode returnMode; /* actual return mode */
189 ExprDoneCond isDone; /* status for ValuePerCall mode */
190 /* fields filled by function in Materialize return mode: */
191 Tuplestorestate *setResult; /* holds the complete returned tuple set */
192 TupleDesc setDesc; /* actual descriptor for returned tuples */
196 * ProjectionInfo node information
198 * This is all the information needed to perform projections ---
199 * that is, form new tuples by evaluation of targetlist expressions.
200 * Nodes which need to do projections create one of these.
202 * ExecProject() evaluates the tlist, forms a tuple, and stores it
203 * in the given slot. Note that the result will be a "virtual" tuple
204 * unless ExecMaterializeSlot() is then called to force it to be
205 * converted to a physical tuple. The slot must have a tupledesc
206 * that matches the output of the tlist!
208 * The planner very often produces tlists that consist entirely of
209 * simple Var references (lower levels of a plan tree almost always
210 * look like that). And top-level tlists are often mostly Vars too.
211 * We therefore optimize execution of simple-Var tlist entries.
212 * The pi_targetlist list actually contains only the tlist entries that
213 * aren't simple Vars, while those that are Vars are processed using the
214 * varSlotOffsets/varNumbers/varOutputCols arrays.
216 * The lastXXXVar fields are used to optimize fetching of fields from
217 * input tuples: they let us do a slot_getsomeattrs() call to ensure
218 * that all needed attributes are extracted in one pass.
220 * targetlist target list for projection (non-Var expressions only)
221 * exprContext expression context in which to evaluate targetlist
222 * slot slot to place projection result in
223 * itemIsDone workspace array for ExecProject
224 * directMap true if varOutputCols[] is an identity map
225 * numSimpleVars number of simple Vars found in original tlist
226 * varSlotOffsets array indicating which slot each simple Var is from
227 * varNumbers array containing input attr numbers of simple Vars
228 * varOutputCols array containing output attr numbers of simple Vars
229 * lastInnerVar highest attnum from inner tuple slot (0 if none)
230 * lastOuterVar highest attnum from outer tuple slot (0 if none)
231 * lastScanVar highest attnum from scan tuple slot (0 if none)
234 typedef struct ProjectionInfo
238 ExprContext *pi_exprContext;
239 TupleTableSlot *pi_slot;
240 ExprDoneCond *pi_itemIsDone;
242 int pi_numSimpleVars;
243 int *pi_varSlotOffsets;
245 int *pi_varOutputCols;
254 * This class is used to store information regarding junk attributes.
255 * A junk attribute is an attribute in a tuple that is needed only for
256 * storing intermediate information in the executor, and does not belong
257 * in emitted tuples. For example, when we do an UPDATE query,
258 * the planner adds a "junk" entry to the targetlist so that the tuples
259 * returned to ExecutePlan() contain an extra attribute: the ctid of
260 * the tuple to be updated. This is needed to do the update, but we
261 * don't want the ctid to be part of the stored new tuple! So, we
262 * apply a "junk filter" to remove the junk attributes and form the
263 * real output tuple. The junkfilter code also provides routines to
264 * extract the values of the junk attribute(s) from the input tuple.
266 * targetList: the original target list (including junk attributes).
267 * cleanTupType: the tuple descriptor for the "clean" tuple (with
268 * junk attributes removed).
269 * cleanMap: A map with the correspondence between the non-junk
270 * attribute numbers of the "original" tuple and the
271 * attribute numbers of the "clean" tuple.
272 * resultSlot: tuple slot used to hold cleaned tuple.
273 * junkAttNo: not used by junkfilter code. Can be used by caller
274 * to remember the attno of a specific junk attribute
275 * (execMain.c stores the "ctid" attno here).
278 typedef struct JunkFilter
282 TupleDesc jf_cleanTupType;
283 AttrNumber *jf_cleanMap;
284 TupleTableSlot *jf_resultSlot;
285 AttrNumber jf_junkAttNo;
289 * ResultRelInfo information
291 * Whenever we update an existing relation, we have to
292 * update indices on the relation, and perhaps also fire triggers.
293 * The ResultRelInfo class is used to hold all the information needed
294 * about a result relation, including indices.. -cim 10/15/89
296 * RangeTableIndex result relation's range table index
297 * RelationDesc relation descriptor for result relation
298 * NumIndices # of indices existing on result relation
299 * IndexRelationDescs array of relation descriptors for indices
300 * IndexRelationInfo array of key/attr info for indices
301 * TrigDesc triggers to be fired, if any
302 * TrigFunctions cached lookup info for trigger functions
303 * TrigWhenExprs array of trigger WHEN expr states
304 * TrigInstrument optional runtime measurements for triggers
305 * ConstraintExprs array of constraint-checking expr states
306 * junkFilter for removing junk attributes from tuples
307 * projectReturning for computing a RETURNING list
310 typedef struct ResultRelInfo
313 Index ri_RangeTableIndex;
314 Relation ri_RelationDesc;
316 RelationPtr ri_IndexRelationDescs;
317 IndexInfo **ri_IndexRelationInfo;
318 TriggerDesc *ri_TrigDesc;
319 FmgrInfo *ri_TrigFunctions;
320 List **ri_TrigWhenExprs;
321 struct Instrumentation *ri_TrigInstrument;
322 List **ri_ConstraintExprs;
323 JunkFilter *ri_junkFilter;
324 ProjectionInfo *ri_projectReturning;
330 * Master working state for an Executor invocation
333 typedef struct EState
337 /* Basic state for all query types: */
338 ScanDirection es_direction; /* current scan direction */
339 Snapshot es_snapshot; /* time qual to use */
340 Snapshot es_crosscheck_snapshot; /* crosscheck time qual for RI */
341 List *es_range_table; /* List of RangeTblEntry */
342 PlannedStmt *es_plannedstmt; /* link to top of plan tree */
344 JunkFilter *es_junkFilter; /* top-level junk filter, if any */
346 /* If query can insert/delete tuples, the command ID to mark them with */
347 CommandId es_output_cid;
349 /* Info about target table for insert/update/delete queries: */
350 ResultRelInfo *es_result_relations; /* array of ResultRelInfos */
351 int es_num_result_relations; /* length of array */
352 ResultRelInfo *es_result_relation_info; /* currently active array elt */
354 /* Stuff used for firing triggers: */
355 List *es_trig_target_relations; /* trigger-only ResultRelInfos */
356 TupleTableSlot *es_trig_tuple_slot; /* for trigger output tuples */
357 TupleTableSlot *es_trig_oldtup_slot; /* for trigger old tuples */
359 /* Parameter info: */
360 ParamListInfo es_param_list_info; /* values of external params */
361 ParamExecData *es_param_exec_vals; /* values of internal params */
363 /* Other working state: */
364 MemoryContext es_query_cxt; /* per-query context in which EState lives */
366 List *es_tupleTable; /* List of TupleTableSlots */
368 List *es_rowMarks; /* List of ExecRowMarks */
370 uint32 es_processed; /* # of tuples processed */
371 Oid es_lastoid; /* last oid processed (by INSERT) */
373 int es_instrument; /* OR of InstrumentOption flags */
374 bool es_select_into; /* true if doing SELECT INTO */
375 bool es_into_oids; /* true to generate OIDs in SELECT INTO */
377 List *es_exprcontexts; /* List of ExprContexts within EState */
379 List *es_subplanstates; /* List of PlanState for SubPlans */
382 * this ExprContext is for per-output-tuple operations, such as constraint
383 * checks and index-value computations. It will be reset for each output
384 * tuple. Note that it will be created only if needed.
386 ExprContext *es_per_tuple_exprcontext;
389 * These fields are for re-evaluating plan quals when an updated tuple is
390 * substituted in READ COMMITTED mode. es_epqTuple[] contains tuples that
391 * scan plan nodes should return instead of whatever they'd normally
392 * return, or NULL if nothing to return; es_epqTupleSet[] is true if a
393 * particular array entry is valid; and es_epqScanDone[] is state to
394 * remember if the tuple has been returned already. Arrays are of size
395 * list_length(es_range_table) and are indexed by scan node scanrelid - 1.
397 HeapTuple *es_epqTuple; /* array of EPQ substitute tuples */
398 bool *es_epqTupleSet; /* true if EPQ tuple is provided */
399 bool *es_epqScanDone; /* true if EPQ tuple has been fetched */
405 * runtime representation of FOR UPDATE/SHARE clauses
407 * When doing UPDATE, DELETE, or SELECT FOR UPDATE/SHARE, we should have an
408 * ExecRowMark for each non-target relation in the query (except inheritance
409 * parent RTEs, which can be ignored at runtime). See PlanRowMark for details
410 * about most of the fields. In addition to fields directly derived from
411 * PlanRowMark, we store curCtid, which is used by the WHERE CURRENT OF code.
413 * EState->es_rowMarks is a list of these structs.
415 typedef struct ExecRowMark
417 Relation relation; /* opened and suitably locked relation */
418 Index rti; /* its range table index */
419 Index prti; /* parent range table index, if child */
420 Index rowmarkId; /* unique identifier for resjunk columns */
421 RowMarkType markType; /* see enum in nodes/plannodes.h */
422 bool noWait; /* NOWAIT option */
423 ItemPointerData curCtid; /* ctid of currently locked tuple, if any */
428 * additional runtime representation of FOR UPDATE/SHARE clauses
430 * Each LockRows and ModifyTable node keeps a list of the rowmarks it needs to
431 * deal with. In addition to a pointer to the related entry in es_rowMarks,
432 * this struct carries the column number(s) of the resjunk columns associated
433 * with the rowmark (see comments for PlanRowMark for more detail). In the
434 * case of ModifyTable, there has to be a separate ExecAuxRowMark list for
435 * each child plan, because the resjunk columns could be at different physical
436 * column positions in different subplans.
438 typedef struct ExecAuxRowMark
440 ExecRowMark *rowmark; /* related entry in es_rowMarks */
441 AttrNumber ctidAttNo; /* resno of ctid junk attribute, if any */
442 AttrNumber toidAttNo; /* resno of tableoid junk attribute, if any */
443 AttrNumber wholeAttNo; /* resno of whole-row junk attribute, if any */
447 /* ----------------------------------------------------------------
450 * All-in-memory tuple hash tables are used for a number of purposes.
452 * Note: tab_hash_funcs are for the key datatype(s) stored in the table,
453 * and tab_eq_funcs are non-cross-type equality operators for those types.
454 * Normally these are the only functions used, but FindTupleHashEntry()
455 * supports searching a hashtable using cross-data-type hashing. For that,
456 * the caller must supply hash functions for the LHS datatype as well as
457 * the cross-type equality operators to use. in_hash_funcs and cur_eq_funcs
458 * are set to point to the caller's function arrays while doing such a search.
459 * During LookupTupleHashEntry(), they point to tab_hash_funcs and
460 * tab_eq_funcs respectively.
461 * ----------------------------------------------------------------
463 typedef struct TupleHashEntryData *TupleHashEntry;
464 typedef struct TupleHashTableData *TupleHashTable;
466 typedef struct TupleHashEntryData
468 /* firstTuple must be the first field in this struct! */
469 MinimalTuple firstTuple; /* copy of first tuple in this group */
470 /* there may be additional data beyond the end of this struct */
471 } TupleHashEntryData; /* VARIABLE LENGTH STRUCT */
473 typedef struct TupleHashTableData
475 HTAB *hashtab; /* underlying dynahash table */
476 int numCols; /* number of columns in lookup key */
477 AttrNumber *keyColIdx; /* attr numbers of key columns */
478 FmgrInfo *tab_hash_funcs; /* hash functions for table datatype(s) */
479 FmgrInfo *tab_eq_funcs; /* equality functions for table datatype(s) */
480 MemoryContext tablecxt; /* memory context containing table */
481 MemoryContext tempcxt; /* context for function evaluations */
482 Size entrysize; /* actual size to make each hash entry */
483 TupleTableSlot *tableslot; /* slot for referencing table entries */
484 /* The following fields are set transiently for each table search: */
485 TupleTableSlot *inputslot; /* current input tuple's slot */
486 FmgrInfo *in_hash_funcs; /* hash functions for input datatype(s) */
487 FmgrInfo *cur_eq_funcs; /* equality functions for input vs. table */
488 } TupleHashTableData;
490 typedef HASH_SEQ_STATUS TupleHashIterator;
493 * Use InitTupleHashIterator/TermTupleHashIterator for a read/write scan.
494 * Use ResetTupleHashIterator if the table can be frozen (in this case no
495 * explicit scan termination is needed).
497 #define InitTupleHashIterator(htable, iter) \
498 hash_seq_init(iter, (htable)->hashtab)
499 #define TermTupleHashIterator(iter) \
501 #define ResetTupleHashIterator(htable, iter) \
503 hash_freeze((htable)->hashtab); \
504 hash_seq_init(iter, (htable)->hashtab); \
506 #define ScanTupleHashTable(iter) \
507 ((TupleHashEntry) hash_seq_search(iter))
510 /* ----------------------------------------------------------------
511 * Expression State Trees
513 * Each executable expression tree has a parallel ExprState tree.
515 * Unlike PlanState, there is not an exact one-for-one correspondence between
516 * ExprState node types and Expr node types. Many Expr node types have no
517 * need for node-type-specific run-time state, and so they can use plain
518 * ExprState or GenericExprState as their associated ExprState node type.
519 * ----------------------------------------------------------------
525 * ExprState is the common superclass for all ExprState-type nodes.
527 * It can also be instantiated directly for leaf Expr nodes that need no
528 * local run-time state (such as Var, Const, or Param).
530 * To save on dispatch overhead, each ExprState node contains a function
531 * pointer to the routine to execute to evaluate the node.
535 typedef struct ExprState ExprState;
537 typedef Datum (*ExprStateEvalFunc) (ExprState *expression,
538 ExprContext *econtext,
540 ExprDoneCond *isDone);
545 Expr *expr; /* associated Expr node */
546 ExprStateEvalFunc evalfunc; /* routine to run to execute node */
550 * GenericExprState node
552 * This is used for Expr node types that need no local run-time state,
553 * but have one child Expr node.
556 typedef struct GenericExprState
559 ExprState *arg; /* state of my child node */
563 * AggrefExprState node
566 typedef struct AggrefExprState
569 List *args; /* states of argument expressions */
570 int aggno; /* ID number for agg within its plan node */
574 * WindowFuncExprState node
577 typedef struct WindowFuncExprState
580 List *args; /* states of argument expressions */
581 int wfuncno; /* ID number for wfunc within its plan node */
582 } WindowFuncExprState;
585 * ArrayRefExprState node
587 * Note: array types can be fixed-length (typlen > 0), but only when the
588 * element type is itself fixed-length. Otherwise they are varlena structures
589 * and have typlen = -1. In any case, an array type is never pass-by-value.
592 typedef struct ArrayRefExprState
595 List *refupperindexpr; /* states for child nodes */
596 List *reflowerindexpr;
598 ExprState *refassgnexpr;
599 int16 refattrlength; /* typlen of array type */
600 int16 refelemlength; /* typlen of the array element type */
601 bool refelembyval; /* is the element type pass-by-value? */
602 char refelemalign; /* typalign of the element type */
608 * Although named for FuncExpr, this is also used for OpExpr, DistinctExpr,
609 * and NullIf nodes; be careful to check what xprstate.expr is actually
613 typedef struct FuncExprState
616 List *args; /* states of argument expressions */
619 * Function manager's lookup info for the target function. If func.fn_oid
620 * is InvalidOid, we haven't initialized it yet (nor any of the following
626 * For a set-returning function (SRF) that returns a tuplestore, we keep
627 * the tuplestore here and dole out the result rows one at a time. The
628 * slot holds the row currently being returned.
630 Tuplestorestate *funcResultStore;
631 TupleTableSlot *funcResultSlot;
634 * In some cases we need to compute a tuple descriptor for the function's
635 * output. If so, it's stored here.
637 TupleDesc funcResultDesc;
638 bool funcReturnsTuple; /* valid when funcResultDesc isn't
642 * setArgsValid is true when we are evaluating a set-returning function
643 * that uses value-per-call mode and we are in the middle of a call
644 * series; we want to pass the same argument values to the function again
645 * (and again, until it returns ExprEndResult). This indicates that
646 * fcinfo_data already contains valid argument data.
651 * Flag to remember whether we found a set-valued argument to the
652 * function. This causes the function result to be a set as well. Valid
653 * only when setArgsValid is true or funcResultStore isn't NULL.
655 bool setHasSetArg; /* some argument returns a set */
658 * Flag to remember whether we have registered a shutdown callback for
659 * this FuncExprState. We do so only if funcResultStore or setArgsValid
660 * has been set at least once (since all the callback is for is to release
661 * the tuplestore or clear setArgsValid).
663 bool shutdown_reg; /* a shutdown callback is registered */
666 * Call parameter structure for the function. This has been initialized
667 * (by InitFunctionCallInfoData) if func.fn_oid is valid. It also saves
668 * argument values between calls, when setArgsValid is true.
670 FunctionCallInfoData fcinfo_data;
674 * ScalarArrayOpExprState node
676 * This is a FuncExprState plus some additional data.
679 typedef struct ScalarArrayOpExprState
681 FuncExprState fxprstate;
682 /* Cached info about array element type */
687 } ScalarArrayOpExprState;
693 typedef struct BoolExprState
696 List *args; /* states of argument expression(s) */
703 typedef struct SubPlanState
706 struct PlanState *planstate; /* subselect plan's state tree */
707 ExprState *testexpr; /* state of combining expression */
708 List *args; /* states of argument expression(s) */
709 HeapTuple curTuple; /* copy of most recent tuple from subplan */
710 /* these are used when hashing the subselect's output: */
711 ProjectionInfo *projLeft; /* for projecting lefthand exprs */
712 ProjectionInfo *projRight; /* for projecting subselect output */
713 TupleHashTable hashtable; /* hash table for no-nulls subselect rows */
714 TupleHashTable hashnulls; /* hash table for rows with null(s) */
715 bool havehashrows; /* TRUE if hashtable is not empty */
716 bool havenullrows; /* TRUE if hashnulls is not empty */
717 MemoryContext hashtablecxt; /* memory context containing hash tables */
718 MemoryContext hashtempcxt; /* temp memory context for hash tables */
719 ExprContext *innerecontext; /* econtext for computing inner tuples */
720 AttrNumber *keyColIdx; /* control data for hash tables */
721 FmgrInfo *tab_hash_funcs; /* hash functions for table datatype(s) */
722 FmgrInfo *tab_eq_funcs; /* equality functions for table datatype(s) */
723 FmgrInfo *lhs_hash_funcs; /* hash functions for lefthand datatype(s) */
724 FmgrInfo *cur_eq_funcs; /* equality functions for LHS vs. table */
728 * AlternativeSubPlanState node
731 typedef struct AlternativeSubPlanState
734 List *subplans; /* states of alternative subplans */
735 int active; /* list index of the one we're using */
736 } AlternativeSubPlanState;
739 * FieldSelectState node
742 typedef struct FieldSelectState
745 ExprState *arg; /* input expression */
746 TupleDesc argdesc; /* tupdesc for most recent input */
750 * FieldStoreState node
753 typedef struct FieldStoreState
756 ExprState *arg; /* input tuple value */
757 List *newvals; /* new value(s) for field(s) */
758 TupleDesc argdesc; /* tupdesc for most recent input */
762 * CoerceViaIOState node
765 typedef struct CoerceViaIOState
768 ExprState *arg; /* input expression */
769 FmgrInfo outfunc; /* lookup info for source output function */
770 FmgrInfo infunc; /* lookup info for result input function */
771 Oid intypioparam; /* argument needed for input function */
775 * ArrayCoerceExprState node
778 typedef struct ArrayCoerceExprState
781 ExprState *arg; /* input array value */
782 Oid resultelemtype; /* element type of result array */
783 FmgrInfo elemfunc; /* lookup info for element coercion function */
784 /* use struct pointer to avoid including array.h here */
785 struct ArrayMapState *amstate; /* workspace for array_map */
786 } ArrayCoerceExprState;
789 * ConvertRowtypeExprState node
792 typedef struct ConvertRowtypeExprState
795 ExprState *arg; /* input tuple value */
796 TupleDesc indesc; /* tupdesc for source rowtype */
797 TupleDesc outdesc; /* tupdesc for result rowtype */
798 /* use "struct" so we needn't include tupconvert.h here */
799 struct TupleConversionMap *map;
801 } ConvertRowtypeExprState;
807 typedef struct CaseExprState
810 ExprState *arg; /* implicit equality comparison argument */
811 List *args; /* the arguments (list of WHEN clauses) */
812 ExprState *defresult; /* the default result (ELSE clause) */
819 typedef struct CaseWhenState
822 ExprState *expr; /* condition expression */
823 ExprState *result; /* substitution result */
827 * ArrayExprState node
829 * Note: ARRAY[] expressions always produce varlena arrays, never fixed-length
833 typedef struct ArrayExprState
836 List *elements; /* states for child nodes */
837 int16 elemlength; /* typlen of the array element type */
838 bool elembyval; /* is the element type pass-by-value? */
839 char elemalign; /* typalign of the element type */
846 typedef struct RowExprState
849 List *args; /* the arguments */
850 TupleDesc tupdesc; /* descriptor for result tuples */
854 * RowCompareExprState node
857 typedef struct RowCompareExprState
860 List *largs; /* the left-hand input arguments */
861 List *rargs; /* the right-hand input arguments */
862 FmgrInfo *funcs; /* array of comparison function info */
863 } RowCompareExprState;
866 * CoalesceExprState node
869 typedef struct CoalesceExprState
872 List *args; /* the arguments */
876 * MinMaxExprState node
879 typedef struct MinMaxExprState
882 List *args; /* the arguments */
883 FmgrInfo cfunc; /* lookup info for comparison func */
890 typedef struct XmlExprState
893 List *named_args; /* ExprStates for named arguments */
894 List *args; /* ExprStates for other arguments */
901 typedef struct NullTestState
904 ExprState *arg; /* input expression */
905 /* used only if input is of composite type: */
906 TupleDesc argdesc; /* tupdesc for most recent input */
910 * CoerceToDomainState node
913 typedef struct CoerceToDomainState
916 ExprState *arg; /* input expression */
917 /* Cached list of constraints that need to be checked */
918 List *constraints; /* list of DomainConstraintState nodes */
919 } CoerceToDomainState;
922 * DomainConstraintState - one item to check during CoerceToDomain
924 * Note: this is just a Node, and not an ExprState, because it has no
925 * corresponding Expr to link to. Nonetheless it is part of an ExprState
926 * tree, so we give it a name following the xxxState convention.
928 typedef enum DomainConstraintType
930 DOM_CONSTRAINT_NOTNULL,
932 } DomainConstraintType;
934 typedef struct DomainConstraintState
937 DomainConstraintType constrainttype; /* constraint type */
938 char *name; /* name of constraint (for error msgs) */
939 ExprState *check_expr; /* for CHECK, a boolean expression */
940 } DomainConstraintState;
943 /* ----------------------------------------------------------------
944 * Executor State Trees
946 * An executing query has a PlanState tree paralleling the Plan tree
947 * that describes the plan.
948 * ----------------------------------------------------------------
954 * We never actually instantiate any PlanState nodes; this is just the common
955 * abstract superclass for all PlanState-type nodes.
958 typedef struct PlanState
962 Plan *plan; /* associated Plan node */
964 EState *state; /* at execution time, states of individual
965 * nodes point to one EState for the whole
968 struct Instrumentation *instrument; /* Optional runtime stats for this
972 * Common structural data for all Plan types. These links to subsidiary
973 * state trees parallel links in the associated plan tree (except for the
974 * subPlan list, which does not exist in the plan tree).
976 List *targetlist; /* target list to be computed at this node */
977 List *qual; /* implicitly-ANDed qual conditions */
978 struct PlanState *lefttree; /* input plan tree(s) */
979 struct PlanState *righttree;
980 List *initPlan; /* Init SubPlanState nodes (un-correlated expr
982 List *subPlan; /* SubPlanState nodes in my expressions */
985 * State for management of parameter-change-driven rescanning
987 Bitmapset *chgParam; /* set of IDs of changed Params */
990 * Other run-time state needed by most if not all node types.
992 TupleTableSlot *ps_ResultTupleSlot; /* slot for my result tuples */
993 ExprContext *ps_ExprContext; /* node's expression-evaluation context */
994 ProjectionInfo *ps_ProjInfo; /* info for doing tuple projection */
995 bool ps_TupFromTlist;/* state flag for processing set-valued
996 * functions in targetlist */
1000 * these are defined to avoid confusion problems with "left"
1001 * and "right" and "inner" and "outer". The convention is that
1002 * the "left" plan is the "outer" plan and the "right" plan is
1003 * the inner plan, but these make the code more readable.
1006 #define innerPlanState(node) (((PlanState *)(node))->righttree)
1007 #define outerPlanState(node) (((PlanState *)(node))->lefttree)
1010 * EPQState is state for executing an EvalPlanQual recheck on a candidate
1011 * tuple in ModifyTable or LockRows. The estate and planstate fields are
1014 typedef struct EPQState
1016 EState *estate; /* subsidiary EState */
1017 PlanState *planstate; /* plan state tree ready to be executed */
1018 TupleTableSlot *origslot; /* original output tuple to be rechecked */
1019 Plan *plan; /* plan tree to be executed */
1020 List *arowMarks; /* ExecAuxRowMarks (non-locking only) */
1021 int epqParam; /* ID of Param to force scan node re-eval */
1026 * ResultState information
1029 typedef struct ResultState
1031 PlanState ps; /* its first field is NodeTag */
1032 ExprState *resconstantqual;
1033 bool rs_done; /* are we done? */
1034 bool rs_checkqual; /* do we need to check the qual? */
1038 * ModifyTableState information
1041 typedef struct ModifyTableState
1043 PlanState ps; /* its first field is NodeTag */
1045 PlanState **mt_plans; /* subplans (one per target rel) */
1046 int mt_nplans; /* number of plans in the array */
1047 int mt_whichplan; /* which one is being executed (0..n-1) */
1048 List **mt_arowmarks; /* per-subplan ExecAuxRowMark lists */
1049 EPQState mt_epqstate; /* for evaluating EvalPlanQual rechecks */
1050 bool fireBSTriggers; /* do we need to fire stmt triggers? */
1054 * AppendState information
1056 * nplans how many plans are in the array
1057 * whichplan which plan is being executed (0 .. n-1)
1060 typedef struct AppendState
1062 PlanState ps; /* its first field is NodeTag */
1063 PlanState **appendplans; /* array of PlanStates for my inputs */
1069 * MergeAppendState information
1071 * nplans how many plans are in the array
1072 * nkeys number of sort key columns
1073 * scankeys sort keys in ScanKey representation
1074 * slots current output tuple of each subplan
1075 * heap heap of active tuples (represented as array indexes)
1076 * heap_size number of active heap entries
1077 * initialized true if we have fetched first tuple from each subplan
1078 * last_slot last subplan fetched from (which must be re-called)
1081 typedef struct MergeAppendState
1083 PlanState ps; /* its first field is NodeTag */
1084 PlanState **mergeplans; /* array of PlanStates for my inputs */
1087 ScanKey ms_scankeys; /* array of length ms_nkeys */
1088 TupleTableSlot **ms_slots; /* array of length ms_nplans */
1089 int *ms_heap; /* array of length ms_nplans */
1090 int ms_heap_size; /* current active length of ms_heap[] */
1091 bool ms_initialized; /* are subplans started? */
1092 int ms_last_slot; /* last subplan slot we returned from */
1096 * RecursiveUnionState information
1098 * RecursiveUnionState is used for performing a recursive union.
1100 * recursing T when we're done scanning the non-recursive term
1101 * intermediate_empty T if intermediate_table is currently empty
1102 * working_table working table (to be scanned by recursive term)
1103 * intermediate_table current recursive output (next generation of WT)
1106 typedef struct RecursiveUnionState
1108 PlanState ps; /* its first field is NodeTag */
1110 bool intermediate_empty;
1111 Tuplestorestate *working_table;
1112 Tuplestorestate *intermediate_table;
1113 /* Remaining fields are unused in UNION ALL case */
1114 FmgrInfo *eqfunctions; /* per-grouping-field equality fns */
1115 FmgrInfo *hashfunctions; /* per-grouping-field hash fns */
1116 MemoryContext tempContext; /* short-term context for comparisons */
1117 TupleHashTable hashtable; /* hash table for tuples already seen */
1118 MemoryContext tableContext; /* memory context containing hash table */
1119 } RecursiveUnionState;
1122 * BitmapAndState information
1125 typedef struct BitmapAndState
1127 PlanState ps; /* its first field is NodeTag */
1128 PlanState **bitmapplans; /* array of PlanStates for my inputs */
1129 int nplans; /* number of input plans */
1133 * BitmapOrState information
1136 typedef struct BitmapOrState
1138 PlanState ps; /* its first field is NodeTag */
1139 PlanState **bitmapplans; /* array of PlanStates for my inputs */
1140 int nplans; /* number of input plans */
1143 /* ----------------------------------------------------------------
1144 * Scan State Information
1145 * ----------------------------------------------------------------
1149 * ScanState information
1151 * ScanState extends PlanState for node types that represent
1152 * scans of an underlying relation. It can also be used for nodes
1153 * that scan the output of an underlying plan node --- in that case,
1154 * only ScanTupleSlot is actually useful, and it refers to the tuple
1155 * retrieved from the subplan.
1157 * currentRelation relation being scanned (NULL if none)
1158 * currentScanDesc current scan descriptor for scan (NULL if none)
1159 * ScanTupleSlot pointer to slot in tuple table holding scan tuple
1162 typedef struct ScanState
1164 PlanState ps; /* its first field is NodeTag */
1165 Relation ss_currentRelation;
1166 HeapScanDesc ss_currentScanDesc;
1167 TupleTableSlot *ss_ScanTupleSlot;
1171 * SeqScan uses a bare ScanState as its state node, since it needs
1172 * no additional fields.
1174 typedef ScanState SeqScanState;
1177 * These structs store information about index quals that don't have simple
1178 * constant right-hand sides. See comments for ExecIndexBuildScanKeys()
1183 ScanKey scan_key; /* scankey to put value into */
1184 ExprState *key_expr; /* expr to evaluate to get value */
1185 bool key_toastable; /* is expr's result a toastable datatype? */
1186 } IndexRuntimeKeyInfo;
1190 ScanKey scan_key; /* scankey to put value into */
1191 ExprState *array_expr; /* expr to evaluate to get array value */
1192 int next_elem; /* next array element to use */
1193 int num_elems; /* number of elems in current array value */
1194 Datum *elem_values; /* array of num_elems Datums */
1195 bool *elem_nulls; /* array of num_elems is-null flags */
1196 } IndexArrayKeyInfo;
1199 * IndexScanState information
1201 * indexqualorig execution state for indexqualorig expressions
1202 * ScanKeys Skey structures for index quals
1203 * NumScanKeys number of ScanKeys
1204 * OrderByKeys Skey structures for index ordering operators
1205 * NumOrderByKeys number of OrderByKeys
1206 * RuntimeKeys info about Skeys that must be evaluated at runtime
1207 * NumRuntimeKeys number of RuntimeKeys
1208 * RuntimeKeysReady true if runtime Skeys have been computed
1209 * RuntimeContext expr context for evaling runtime Skeys
1210 * RelationDesc index relation descriptor
1211 * ScanDesc index scan descriptor
1214 typedef struct IndexScanState
1216 ScanState ss; /* its first field is NodeTag */
1217 List *indexqualorig;
1218 ScanKey iss_ScanKeys;
1219 int iss_NumScanKeys;
1220 ScanKey iss_OrderByKeys;
1221 int iss_NumOrderByKeys;
1222 IndexRuntimeKeyInfo *iss_RuntimeKeys;
1223 int iss_NumRuntimeKeys;
1224 bool iss_RuntimeKeysReady;
1225 ExprContext *iss_RuntimeContext;
1226 Relation iss_RelationDesc;
1227 IndexScanDesc iss_ScanDesc;
1231 * BitmapIndexScanState information
1233 * result bitmap to return output into, or NULL
1234 * ScanKeys Skey structures for index quals
1235 * NumScanKeys number of ScanKeys
1236 * RuntimeKeys info about Skeys that must be evaluated at runtime
1237 * NumRuntimeKeys number of RuntimeKeys
1238 * ArrayKeys info about Skeys that come from ScalarArrayOpExprs
1239 * NumArrayKeys number of ArrayKeys
1240 * RuntimeKeysReady true if runtime Skeys have been computed
1241 * RuntimeContext expr context for evaling runtime Skeys
1242 * RelationDesc index relation descriptor
1243 * ScanDesc index scan descriptor
1246 typedef struct BitmapIndexScanState
1248 ScanState ss; /* its first field is NodeTag */
1249 TIDBitmap *biss_result;
1250 ScanKey biss_ScanKeys;
1251 int biss_NumScanKeys;
1252 IndexRuntimeKeyInfo *biss_RuntimeKeys;
1253 int biss_NumRuntimeKeys;
1254 IndexArrayKeyInfo *biss_ArrayKeys;
1255 int biss_NumArrayKeys;
1256 bool biss_RuntimeKeysReady;
1257 ExprContext *biss_RuntimeContext;
1258 Relation biss_RelationDesc;
1259 IndexScanDesc biss_ScanDesc;
1260 } BitmapIndexScanState;
1263 * BitmapHeapScanState information
1265 * bitmapqualorig execution state for bitmapqualorig expressions
1266 * tbm bitmap obtained from child index scan(s)
1267 * tbmiterator iterator for scanning current pages
1268 * tbmres current-page data
1269 * prefetch_iterator iterator for prefetching ahead of current page
1270 * prefetch_pages # pages prefetch iterator is ahead of current
1271 * prefetch_target target prefetch distance
1274 typedef struct BitmapHeapScanState
1276 ScanState ss; /* its first field is NodeTag */
1277 List *bitmapqualorig;
1279 TBMIterator *tbmiterator;
1280 TBMIterateResult *tbmres;
1281 TBMIterator *prefetch_iterator;
1283 int prefetch_target;
1284 } BitmapHeapScanState;
1287 * TidScanState information
1289 * isCurrentOf scan has a CurrentOfExpr qual
1290 * NumTids number of tids in this scan
1291 * TidPtr index of currently fetched tid
1292 * TidList evaluated item pointers (array of size NumTids)
1295 typedef struct TidScanState
1297 ScanState ss; /* its first field is NodeTag */
1298 List *tss_tidquals; /* list of ExprState nodes */
1299 bool tss_isCurrentOf;
1303 ItemPointerData *tss_TidList;
1304 HeapTupleData tss_htup;
1308 * SubqueryScanState information
1310 * SubqueryScanState is used for scanning a sub-query in the range table.
1311 * ScanTupleSlot references the current output tuple of the sub-query.
1314 typedef struct SubqueryScanState
1316 ScanState ss; /* its first field is NodeTag */
1318 } SubqueryScanState;
1321 * FunctionScanState information
1323 * Function nodes are used to scan the results of a
1324 * function appearing in FROM (typically a function returning set).
1326 * eflags node's capability flags
1327 * tupdesc expected return tuple description
1328 * tuplestorestate private state of tuplestore.c
1329 * funcexpr state for function expression being evaluated
1332 typedef struct FunctionScanState
1334 ScanState ss; /* its first field is NodeTag */
1337 Tuplestorestate *tuplestorestate;
1338 ExprState *funcexpr;
1339 } FunctionScanState;
1342 * ValuesScanState information
1344 * ValuesScan nodes are used to scan the results of a VALUES list
1346 * rowcontext per-expression-list context
1347 * exprlists array of expression lists being evaluated
1348 * array_len size of array
1349 * curr_idx current array index (0-based)
1350 * marked_idx marked position (for mark/restore)
1352 * Note: ss.ps.ps_ExprContext is used to evaluate any qual or projection
1353 * expressions attached to the node. We create a second ExprContext,
1354 * rowcontext, in which to build the executor expression state for each
1355 * Values sublist. Resetting this context lets us get rid of expression
1356 * state for each row, avoiding major memory leakage over a long values list.
1359 typedef struct ValuesScanState
1361 ScanState ss; /* its first field is NodeTag */
1362 ExprContext *rowcontext;
1370 * CteScanState information
1372 * CteScan nodes are used to scan a CommonTableExpr query.
1374 * Multiple CteScan nodes can read out from the same CTE query. We use
1375 * a tuplestore to hold rows that have been read from the CTE query but
1376 * not yet consumed by all readers.
1379 typedef struct CteScanState
1381 ScanState ss; /* its first field is NodeTag */
1382 int eflags; /* capability flags to pass to tuplestore */
1383 int readptr; /* index of my tuplestore read pointer */
1384 PlanState *cteplanstate; /* PlanState for the CTE query itself */
1385 /* Link to the "leader" CteScanState (possibly this same node) */
1386 struct CteScanState *leader;
1387 /* The remaining fields are only valid in the "leader" CteScanState */
1388 Tuplestorestate *cte_table; /* rows already read from the CTE query */
1389 bool eof_cte; /* reached end of CTE query? */
1393 * WorkTableScanState information
1395 * WorkTableScan nodes are used to scan the work table created by
1396 * a RecursiveUnion node. We locate the RecursiveUnion node
1397 * during executor startup.
1400 typedef struct WorkTableScanState
1402 ScanState ss; /* its first field is NodeTag */
1403 RecursiveUnionState *rustate;
1404 } WorkTableScanState;
1407 * ForeignScanState information
1409 * ForeignScan nodes are used to scan foreign-data tables.
1412 typedef struct ForeignScanState
1414 ScanState ss; /* its first field is NodeTag */
1415 /* use struct pointer to avoid including fdwapi.h here */
1416 struct FdwRoutine *fdwroutine;
1417 void *fdw_state; /* foreign-data wrapper can keep state here */
1420 /* ----------------------------------------------------------------
1421 * Join State Information
1422 * ----------------------------------------------------------------
1426 * JoinState information
1428 * Superclass for state nodes of join plans.
1431 typedef struct JoinState
1435 List *joinqual; /* JOIN quals (in addition to ps.qual) */
1439 * NestLoopState information
1441 * NeedNewOuter true if need new outer tuple on next call
1442 * MatchedOuter true if found a join match for current outer tuple
1443 * NullInnerTupleSlot prepared null tuple for left outer joins
1446 typedef struct NestLoopState
1448 JoinState js; /* its first field is NodeTag */
1449 bool nl_NeedNewOuter;
1450 bool nl_MatchedOuter;
1451 TupleTableSlot *nl_NullInnerTupleSlot;
1455 * MergeJoinState information
1457 * NumClauses number of mergejoinable join clauses
1458 * Clauses info for each mergejoinable clause
1459 * JoinState current state of ExecMergeJoin state machine
1460 * ExtraMarks true to issue extra Mark operations on inner scan
1461 * ConstFalseJoin true if we have a constant-false joinqual
1462 * FillOuter true if should emit unjoined outer tuples anyway
1463 * FillInner true if should emit unjoined inner tuples anyway
1464 * MatchedOuter true if found a join match for current outer tuple
1465 * MatchedInner true if found a join match for current inner tuple
1466 * OuterTupleSlot slot in tuple table for cur outer tuple
1467 * InnerTupleSlot slot in tuple table for cur inner tuple
1468 * MarkedTupleSlot slot in tuple table for marked tuple
1469 * NullOuterTupleSlot prepared null tuple for right outer joins
1470 * NullInnerTupleSlot prepared null tuple for left outer joins
1471 * OuterEContext workspace for computing outer tuple's join values
1472 * InnerEContext workspace for computing inner tuple's join values
1475 /* private in nodeMergejoin.c: */
1476 typedef struct MergeJoinClauseData *MergeJoinClause;
1478 typedef struct MergeJoinState
1480 JoinState js; /* its first field is NodeTag */
1482 MergeJoinClause mj_Clauses; /* array of length mj_NumClauses */
1485 bool mj_ConstFalseJoin;
1488 bool mj_MatchedOuter;
1489 bool mj_MatchedInner;
1490 TupleTableSlot *mj_OuterTupleSlot;
1491 TupleTableSlot *mj_InnerTupleSlot;
1492 TupleTableSlot *mj_MarkedTupleSlot;
1493 TupleTableSlot *mj_NullOuterTupleSlot;
1494 TupleTableSlot *mj_NullInnerTupleSlot;
1495 ExprContext *mj_OuterEContext;
1496 ExprContext *mj_InnerEContext;
1500 * HashJoinState information
1502 * hashclauses original form of the hashjoin condition
1503 * hj_OuterHashKeys the outer hash keys in the hashjoin condition
1504 * hj_InnerHashKeys the inner hash keys in the hashjoin condition
1505 * hj_HashOperators the join operators in the hashjoin condition
1506 * hj_HashTable hash table for the hashjoin
1507 * (NULL if table not built yet)
1508 * hj_CurHashValue hash value for current outer tuple
1509 * hj_CurBucketNo regular bucket# for current outer tuple
1510 * hj_CurSkewBucketNo skew bucket# for current outer tuple
1511 * hj_CurTuple last inner tuple matched to current outer
1512 * tuple, or NULL if starting search
1513 * (hj_CurXXX variables are undefined if
1514 * OuterTupleSlot is empty!)
1515 * hj_OuterTupleSlot tuple slot for outer tuples
1516 * hj_HashTupleSlot tuple slot for inner (hashed) tuples
1517 * hj_NullOuterTupleSlot prepared null tuple for right/full outer joins
1518 * hj_NullInnerTupleSlot prepared null tuple for left/full outer joins
1519 * hj_FirstOuterTupleSlot first tuple retrieved from outer plan
1520 * hj_JoinState current state of ExecHashJoin state machine
1521 * hj_MatchedOuter true if found a join match for current outer
1522 * hj_OuterNotEmpty true if outer relation known not empty
1526 /* these structs are defined in executor/hashjoin.h: */
1527 typedef struct HashJoinTupleData *HashJoinTuple;
1528 typedef struct HashJoinTableData *HashJoinTable;
1530 typedef struct HashJoinState
1532 JoinState js; /* its first field is NodeTag */
1533 List *hashclauses; /* list of ExprState nodes */
1534 List *hj_OuterHashKeys; /* list of ExprState nodes */
1535 List *hj_InnerHashKeys; /* list of ExprState nodes */
1536 List *hj_HashOperators; /* list of operator OIDs */
1537 HashJoinTable hj_HashTable;
1538 uint32 hj_CurHashValue;
1540 int hj_CurSkewBucketNo;
1541 HashJoinTuple hj_CurTuple;
1542 TupleTableSlot *hj_OuterTupleSlot;
1543 TupleTableSlot *hj_HashTupleSlot;
1544 TupleTableSlot *hj_NullOuterTupleSlot;
1545 TupleTableSlot *hj_NullInnerTupleSlot;
1546 TupleTableSlot *hj_FirstOuterTupleSlot;
1548 bool hj_MatchedOuter;
1549 bool hj_OuterNotEmpty;
1553 /* ----------------------------------------------------------------
1554 * Materialization State Information
1555 * ----------------------------------------------------------------
1559 * MaterialState information
1561 * materialize nodes are used to materialize the results
1562 * of a subplan into a temporary file.
1564 * ss.ss_ScanTupleSlot refers to output of underlying plan.
1567 typedef struct MaterialState
1569 ScanState ss; /* its first field is NodeTag */
1570 int eflags; /* capability flags to pass to tuplestore */
1571 bool eof_underlying; /* reached end of underlying plan? */
1572 Tuplestorestate *tuplestorestate;
1576 * SortState information
1579 typedef struct SortState
1581 ScanState ss; /* its first field is NodeTag */
1582 bool randomAccess; /* need random access to sort output? */
1583 bool bounded; /* is the result set bounded? */
1584 int64 bound; /* if bounded, how many tuples are needed */
1585 bool sort_Done; /* sort completed yet? */
1586 bool bounded_Done; /* value of bounded we did the sort with */
1587 int64 bound_Done; /* value of bound we did the sort with */
1588 void *tuplesortstate; /* private state of tuplesort.c */
1591 /* ---------------------
1592 * GroupState information
1593 * -------------------------
1595 typedef struct GroupState
1597 ScanState ss; /* its first field is NodeTag */
1598 FmgrInfo *eqfunctions; /* per-field lookup data for equality fns */
1599 bool grp_done; /* indicates completion of Group scan */
1602 /* ---------------------
1603 * AggState information
1605 * ss.ss_ScanTupleSlot refers to output of underlying plan.
1607 * Note: ss.ps.ps_ExprContext contains ecxt_aggvalues and
1608 * ecxt_aggnulls arrays, which hold the computed agg values for the current
1609 * input group during evaluation of an Agg node's output tuple(s). We
1610 * create a second ExprContext, tmpcontext, in which to evaluate input
1611 * expressions and run the aggregate transition functions.
1612 * -------------------------
1614 /* these structs are private in nodeAgg.c: */
1615 typedef struct AggStatePerAggData *AggStatePerAgg;
1616 typedef struct AggStatePerGroupData *AggStatePerGroup;
1618 typedef struct AggState
1620 ScanState ss; /* its first field is NodeTag */
1621 List *aggs; /* all Aggref nodes in targetlist & quals */
1622 int numaggs; /* length of list (could be zero!) */
1623 FmgrInfo *eqfunctions; /* per-grouping-field equality fns */
1624 FmgrInfo *hashfunctions; /* per-grouping-field hash fns */
1625 AggStatePerAgg peragg; /* per-Aggref information */
1626 MemoryContext aggcontext; /* memory context for long-lived data */
1627 ExprContext *tmpcontext; /* econtext for input expressions */
1628 bool agg_done; /* indicates completion of Agg scan */
1629 /* these fields are used in AGG_PLAIN and AGG_SORTED modes: */
1630 AggStatePerGroup pergroup; /* per-Aggref-per-group working state */
1631 HeapTuple grp_firstTuple; /* copy of first tuple of current group */
1632 /* these fields are used in AGG_HASHED mode: */
1633 TupleHashTable hashtable; /* hash table with one entry per group */
1634 TupleTableSlot *hashslot; /* slot for loading hash table */
1635 List *hash_needed; /* list of columns needed in hash table */
1636 bool table_filled; /* hash table filled yet? */
1637 TupleHashIterator hashiter; /* for iterating through hash table */
1641 * WindowAggState information
1644 /* these structs are private in nodeWindowAgg.c: */
1645 typedef struct WindowStatePerFuncData *WindowStatePerFunc;
1646 typedef struct WindowStatePerAggData *WindowStatePerAgg;
1648 typedef struct WindowAggState
1650 ScanState ss; /* its first field is NodeTag */
1652 /* these fields are filled in by ExecInitExpr: */
1653 List *funcs; /* all WindowFunc nodes in targetlist */
1654 int numfuncs; /* total number of window functions */
1655 int numaggs; /* number that are plain aggregates */
1657 WindowStatePerFunc perfunc; /* per-window-function information */
1658 WindowStatePerAgg peragg; /* per-plain-aggregate information */
1659 FmgrInfo *partEqfunctions; /* equality funcs for partition columns */
1660 FmgrInfo *ordEqfunctions; /* equality funcs for ordering columns */
1661 Tuplestorestate *buffer; /* stores rows of current partition */
1662 int current_ptr; /* read pointer # for current */
1663 int64 spooled_rows; /* total # of rows in buffer */
1664 int64 currentpos; /* position of current row in partition */
1665 int64 frameheadpos; /* current frame head position */
1666 int64 frametailpos; /* current frame tail position */
1667 /* use struct pointer to avoid including windowapi.h here */
1668 struct WindowObjectData *agg_winobj; /* winobj for aggregate
1670 int64 aggregatedbase; /* start row for current aggregates */
1671 int64 aggregatedupto; /* rows before this one are aggregated */
1673 int frameOptions; /* frame_clause options, see WindowDef */
1674 ExprState *startOffset; /* expression for starting bound offset */
1675 ExprState *endOffset; /* expression for ending bound offset */
1676 Datum startOffsetValue; /* result of startOffset evaluation */
1677 Datum endOffsetValue; /* result of endOffset evaluation */
1679 MemoryContext partcontext; /* context for partition-lifespan data */
1680 MemoryContext aggcontext; /* context for each aggregate data */
1681 ExprContext *tmpcontext; /* short-term evaluation context */
1683 bool all_first; /* true if the scan is starting */
1684 bool all_done; /* true if the scan is finished */
1685 bool partition_spooled; /* true if all tuples in current
1686 * partition have been spooled into
1688 bool more_partitions;/* true if there's more partitions after this
1690 bool framehead_valid;/* true if frameheadpos is known up to date
1691 * for current row */
1692 bool frametail_valid;/* true if frametailpos is known up to date
1693 * for current row */
1695 TupleTableSlot *first_part_slot; /* first tuple of current or next
1698 /* temporary slots for tuples fetched back from tuplestore */
1699 TupleTableSlot *agg_row_slot;
1700 TupleTableSlot *temp_slot_1;
1701 TupleTableSlot *temp_slot_2;
1705 * UniqueState information
1707 * Unique nodes are used "on top of" sort nodes to discard
1708 * duplicate tuples returned from the sort phase. Basically
1709 * all it does is compare the current tuple from the subplan
1710 * with the previously fetched tuple (stored in its result slot).
1711 * If the two are identical in all interesting fields, then
1712 * we just fetch another tuple from the sort and try again.
1715 typedef struct UniqueState
1717 PlanState ps; /* its first field is NodeTag */
1718 FmgrInfo *eqfunctions; /* per-field lookup data for equality fns */
1719 MemoryContext tempContext; /* short-term context for comparisons */
1723 * HashState information
1726 typedef struct HashState
1728 PlanState ps; /* its first field is NodeTag */
1729 HashJoinTable hashtable; /* hash table for the hashjoin */
1730 List *hashkeys; /* list of ExprState nodes */
1731 /* hashkeys is same as parent's hj_InnerHashKeys */
1735 * SetOpState information
1737 * Even in "sorted" mode, SetOp nodes are more complex than a simple
1738 * Unique, since we have to count how many duplicates to return. But
1739 * we also support hashing, so this is really more like a cut-down
1743 /* this struct is private in nodeSetOp.c: */
1744 typedef struct SetOpStatePerGroupData *SetOpStatePerGroup;
1746 typedef struct SetOpState
1748 PlanState ps; /* its first field is NodeTag */
1749 FmgrInfo *eqfunctions; /* per-grouping-field equality fns */
1750 FmgrInfo *hashfunctions; /* per-grouping-field hash fns */
1751 bool setop_done; /* indicates completion of output scan */
1752 long numOutput; /* number of dups left to output */
1753 MemoryContext tempContext; /* short-term context for comparisons */
1754 /* these fields are used in SETOP_SORTED mode: */
1755 SetOpStatePerGroup pergroup; /* per-group working state */
1756 HeapTuple grp_firstTuple; /* copy of first tuple of current group */
1757 /* these fields are used in SETOP_HASHED mode: */
1758 TupleHashTable hashtable; /* hash table with one entry per group */
1759 MemoryContext tableContext; /* memory context containing hash table */
1760 bool table_filled; /* hash table filled yet? */
1761 TupleHashIterator hashiter; /* for iterating through hash table */
1765 * LockRowsState information
1767 * LockRows nodes are used to enforce FOR UPDATE/FOR SHARE locking.
1770 typedef struct LockRowsState
1772 PlanState ps; /* its first field is NodeTag */
1773 List *lr_arowMarks; /* List of ExecAuxRowMarks */
1774 EPQState lr_epqstate; /* for evaluating EvalPlanQual rechecks */
1778 * LimitState information
1780 * Limit nodes are used to enforce LIMIT/OFFSET clauses.
1781 * They just select the desired subrange of their subplan's output.
1783 * offset is the number of initial tuples to skip (0 does nothing).
1784 * count is the number of tuples to return after skipping the offset tuples.
1785 * If no limit count was specified, count is undefined and noCount is true.
1786 * When lstate == LIMIT_INITIAL, offset/count/noCount haven't been set yet.
1791 LIMIT_INITIAL, /* initial state for LIMIT node */
1792 LIMIT_RESCAN, /* rescan after recomputing parameters */
1793 LIMIT_EMPTY, /* there are no returnable rows */
1794 LIMIT_INWINDOW, /* have returned a row in the window */
1795 LIMIT_SUBPLANEOF, /* at EOF of subplan (within window) */
1796 LIMIT_WINDOWEND, /* stepped off end of window */
1797 LIMIT_WINDOWSTART /* stepped off beginning of window */
1800 typedef struct LimitState
1802 PlanState ps; /* its first field is NodeTag */
1803 ExprState *limitOffset; /* OFFSET parameter, or NULL if none */
1804 ExprState *limitCount; /* COUNT parameter, or NULL if none */
1805 int64 offset; /* current OFFSET value */
1806 int64 count; /* current COUNT, if any */
1807 bool noCount; /* if true, ignore count */
1808 LimitStateCond lstate; /* state machine status, as above */
1809 int64 position; /* 1-based index of last tuple returned */
1810 TupleTableSlot *subSlot; /* tuple last obtained from subplan */
1813 #endif /* EXECNODES_H */