plannodes.h File Reference

#include "access/sdir.h"
#include "access/stratnum.h"
#include "nodes/bitmapset.h"
#include "nodes/lockoptions.h"
#include "nodes/primnodes.h"

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Data Structures
struct	PlannedStmt
struct	Plan
struct	Result
struct	ProjectSet
struct	ModifyTable
struct	Append
struct	MergeAppend
struct	RecursiveUnion
struct	BitmapAnd
struct	BitmapOr
struct	Scan
struct	SeqScan
struct	SampleScan
struct	IndexScan
struct	IndexOnlyScan
struct	BitmapIndexScan
struct	BitmapHeapScan
struct	TidScan
struct	TidRangeScan
struct	SubqueryScan
struct	FunctionScan
struct	ValuesScan
struct	TableFuncScan
struct	CteScan
struct	NamedTuplestoreScan
struct	WorkTableScan
struct	ForeignScan
struct	CustomScan
struct	Join
struct	NestLoop
struct	NestLoopParam
struct	MergeJoin
struct	HashJoin
struct	Material
struct	Memoize
struct	Sort
struct	IncrementalSort
struct	Group
struct	Agg
struct	WindowAgg
struct	Unique
struct	Gather
struct	GatherMerge
struct	Hash
struct	SetOp
struct	LockRows
struct	Limit
struct	PlanRowMark
struct	PartitionPruneInfo
struct	PartitionedRelPruneInfo
struct	PartitionPruneStep
struct	PartitionPruneStepOp
struct	PartitionPruneStepCombine
struct	PlanInvalItem
struct	SubPlanRTInfo
struct	ElidedNode

Macros
#define	exec_subplan_get_plan(plannedstmt, subplan)    ((Plan *) list_nth((plannedstmt)->subplans, (subplan)->plan_id - 1))
#define	innerPlan(node)   (((Plan *)(node))->righttree)
#define	outerPlan(node)   (((Plan *)(node))->lefttree)
#define	RowMarkRequiresRowShareLock(marktype)   ((marktype) <= ROW_MARK_KEYSHARE)

Typedefs
typedef enum PlannedStmtOrigin	PlannedStmtOrigin
typedef struct PlannedStmt	PlannedStmt
typedef struct Plan	Plan
typedef enum ResultType	ResultType
typedef struct Result	Result
typedef struct ProjectSet	ProjectSet
typedef struct ModifyTable	ModifyTable
typedef struct Append	Append
typedef struct MergeAppend	MergeAppend
typedef struct RecursiveUnion	RecursiveUnion
typedef struct BitmapAnd	BitmapAnd
typedef struct BitmapOr	BitmapOr
typedef struct Scan	Scan
typedef struct SeqScan	SeqScan
typedef struct SampleScan	SampleScan
typedef struct IndexScan	IndexScan
typedef struct IndexOnlyScan	IndexOnlyScan
typedef struct BitmapIndexScan	BitmapIndexScan
typedef struct BitmapHeapScan	BitmapHeapScan
typedef struct TidScan	TidScan
typedef struct TidRangeScan	TidRangeScan
typedef enum SubqueryScanStatus	SubqueryScanStatus
typedef struct SubqueryScan	SubqueryScan
typedef struct FunctionScan	FunctionScan
typedef struct ValuesScan	ValuesScan
typedef struct TableFuncScan	TableFuncScan
typedef struct CteScan	CteScan
typedef struct NamedTuplestoreScan	NamedTuplestoreScan
typedef struct WorkTableScan	WorkTableScan
typedef struct ForeignScan	ForeignScan
typedef struct CustomScan	CustomScan
typedef struct Join	Join
typedef struct NestLoop	NestLoop
typedef struct NestLoopParam	NestLoopParam
typedef struct MergeJoin	MergeJoin
typedef struct HashJoin	HashJoin
typedef struct Material	Material
typedef struct Memoize	Memoize
typedef struct Sort	Sort
typedef struct IncrementalSort	IncrementalSort
typedef struct Group	Group
typedef struct Agg	Agg
typedef struct WindowAgg	WindowAgg
typedef struct Unique	Unique
typedef struct Gather	Gather
typedef struct GatherMerge	GatherMerge
typedef struct Hash	Hash
typedef struct SetOp	SetOp
typedef struct LockRows	LockRows
typedef struct Limit	Limit
typedef enum RowMarkType	RowMarkType
typedef struct PlanRowMark	PlanRowMark
typedef struct PartitionPruneInfo	PartitionPruneInfo
typedef struct PartitionedRelPruneInfo	PartitionedRelPruneInfo
typedef struct PartitionPruneStep	PartitionPruneStep
typedef struct PartitionPruneStepOp	PartitionPruneStepOp
typedef enum PartitionPruneCombineOp	PartitionPruneCombineOp
typedef struct PartitionPruneStepCombine	PartitionPruneStepCombine
typedef struct PlanInvalItem	PlanInvalItem
typedef enum MonotonicFunction	MonotonicFunction
typedef struct SubPlanRTInfo	SubPlanRTInfo
typedef struct ElidedNode	ElidedNode

Enumerations
enum	PlannedStmtOrigin {   PLAN_STMT_UNKNOWN = 0 , PLAN_STMT_INTERNAL , PLAN_STMT_STANDARD , PLAN_STMT_CACHE_GENERIC ,   PLAN_STMT_CACHE_CUSTOM }
enum	ResultType {   RESULT_TYPE_GATING , RESULT_TYPE_SCAN , RESULT_TYPE_JOIN , RESULT_TYPE_UPPER ,   RESULT_TYPE_MINMAX }
enum	SubqueryScanStatus { SUBQUERY_SCAN_UNKNOWN , SUBQUERY_SCAN_TRIVIAL , SUBQUERY_SCAN_NONTRIVIAL }
enum	RowMarkType {   ROW_MARK_EXCLUSIVE , ROW_MARK_NOKEYEXCLUSIVE , ROW_MARK_SHARE , ROW_MARK_KEYSHARE ,   ROW_MARK_REFERENCE , ROW_MARK_COPY }
enum	PartitionPruneCombineOp { PARTPRUNE_COMBINE_UNION , PARTPRUNE_COMBINE_INTERSECT }
enum	MonotonicFunction { MONOTONICFUNC_NONE = 0 , MONOTONICFUNC_INCREASING = (1 << 0) , MONOTONICFUNC_DECREASING = (1 << 1) , MONOTONICFUNC_BOTH = MONOTONICFUNC_INCREASING | MONOTONICFUNC_DECREASING }

Macro Definition Documentation

exec_subplan_get_plan

#define exec_subplan_get_plan	(		plannedstmt,
			subplan
	)		((Plan *) list_nth((plannedstmt)->subplans, (subplan)->plan_id - 1))

Definition at line 175 of file plannodes.h.

{
    pg_node_attr(abstract, no_equal, no_query_jumble)
 
    NodeTag     type;
 
    /*
     * estimated execution costs for plan (see costsize.c for more info)
     */
    /* count of disabled nodes */
    int         disabled_nodes;
    /* cost expended before fetching any tuples */
    Cost        startup_cost;
    /* total cost (assuming all tuples fetched) */
    Cost        total_cost;
 
    /*
     * planner's estimate of result size of this plan step
     */
    /* number of rows plan is expected to emit */
    Cardinality plan_rows;
    /* average row width in bytes */
    int         plan_width;
 
    /*
     * information needed for parallel query
     */
    /* engage parallel-aware logic? */
    bool        parallel_aware;
    /* OK to use as part of parallel plan? */
    bool        parallel_safe;
 
    /*
     * information needed for asynchronous execution
     */
    /* engage asynchronous-capable logic? */
    bool        async_capable;
 
    /*
     * Common structural data for all Plan types.
     */
    /* unique across entire final plan tree */
    int         plan_node_id;
    /* target list to be computed at this node */
    List       *targetlist;
    /* implicitly-ANDed qual conditions */
    List       *qual;
    /* input plan tree(s) */
    struct Plan *lefttree;
    struct Plan *righttree;
    /* Init Plan nodes (un-correlated expr subselects) */
    List       *initPlan;
 
    /*
     * Information for management of parameter-change-driven rescanning
     *
     * extParam includes the paramIDs of all external PARAM_EXEC params
     * affecting this plan node or its children.  setParam params from the
     * node's initPlans are not included, but their extParams are.
     *
     * allParam includes all the extParam paramIDs, plus the IDs of local
     * params that affect the node (i.e., the setParams of its initplans).
     * These are _all_ the PARAM_EXEC params that affect this node.
     */
    Bitmapset  *extParam;
    Bitmapset  *allParam;
} Plan;
 
/* ----------------
 *  these are defined to avoid confusion problems with "left"
 *  and "right" and "inner" and "outer".  The convention is that
 *  the "left" plan is the "outer" plan and the "right" plan is
 *  the inner plan, but these make the code more readable.
 * ----------------
 */
#define innerPlan(node)         (((Plan *)(node))->righttree)
#define outerPlan(node)         (((Plan *)(node))->lefttree)
 
 
/* ----------------
 *   ResultType -
 *      Classification of Result nodes
 * ----------------
 */
typedef enum ResultType
{
    RESULT_TYPE_GATING,         /* project or one-time-filter outer plan */
    RESULT_TYPE_SCAN,           /* replace empty scan */
    RESULT_TYPE_JOIN,           /* replace empty join */
    RESULT_TYPE_UPPER,          /* replace degenerate upper rel */
    RESULT_TYPE_MINMAX          /* implement minmax aggregate */
} ResultType;
 
/* ----------------
 *   Result node -
 *      If no outer plan, evaluate a variable-free targetlist.
 *      If outer plan, return tuples from outer plan (after a level of
 *      projection as shown by targetlist).
 *
 * If resconstantqual isn't NULL, it represents a one-time qualification
 * test (i.e., one that doesn't depend on any variables from the outer plan,
 * so needs to be evaluated only once).
 *
 * relids identifies the relation for which this Result node is generating the
 * tuples. When subplan is not NULL, it should be empty: this node is not
 * generating anything in that case, just acting on tuples generated by the
 * subplan. Otherwise, it contains the relids of the planner relation that
 * the Result represents.
 * ----------------
 */
typedef struct Result
{
    Plan        plan;
    ResultType  result_type;
    Node       *resconstantqual;
    Bitmapset  *relids;
} Result;
 
/* ----------------
 *   ProjectSet node -
 *      Apply a projection that includes set-returning functions to the
 *      output tuples of the outer plan.
 * ----------------
 */
typedef struct ProjectSet
{
    Plan        plan;
} ProjectSet;
 
/* ----------------
 *   ModifyTable node -
 *      Apply rows produced by outer plan to result table(s),
 *      by inserting, updating, or deleting.
 *
 * If the originally named target table is a partitioned table or inheritance
 * tree, both nominalRelation and rootRelation contain the RT index of the
 * partition root or appendrel RTE, which is not otherwise mentioned in the
 * plan.  Otherwise rootRelation is zero.  However, nominalRelation will
 * always be set, as it's the rel that EXPLAIN should claim is the
 * INSERT/UPDATE/DELETE/MERGE target.
 *
 * Note that rowMarks and epqParam are presumed to be valid for all the
 * table(s); they can't contain any info that varies across tables.
 * ----------------
 */
typedef struct ModifyTable
{
    Plan        plan;
    /* INSERT, UPDATE, DELETE, or MERGE */
    CmdType     operation;
    /* do we set the command tag/es_processed? */
    bool        canSetTag;
    /* Parent RT index for use of EXPLAIN */
    Index       nominalRelation;
    /* Root RT index, if partitioned/inherited */
    Index       rootRelation;
    /* integer list of RT indexes */
    List       *resultRelations;
    /* per-target-table update_colnos lists */
    List       *updateColnosLists;
    /* per-target-table WCO lists */
    List       *withCheckOptionLists;
    /* alias for OLD in RETURNING lists */
    char       *returningOldAlias;
    /* alias for NEW in RETURNING lists */
    char       *returningNewAlias;
    /* per-target-table RETURNING tlists */
    List       *returningLists;
    /* per-target-table FDW private data lists */
    List       *fdwPrivLists;
    /* indices of FDW DM plans */
    Bitmapset  *fdwDirectModifyPlans;
    /* PlanRowMarks (non-locking only) */
    List       *rowMarks;
    /* ID of Param for EvalPlanQual re-eval */
    int         epqParam;
    /* ON CONFLICT action */
    OnConflictAction onConflictAction;
    /* List of ON CONFLICT arbiter index OIDs  */
    List       *arbiterIndexes;
    /* lock strength for ON CONFLICT DO SELECT */
    LockClauseStrength onConflictLockStrength;
    /* INSERT ON CONFLICT DO UPDATE targetlist */
    List       *onConflictSet;
    /* target column numbers for onConflictSet */
    List       *onConflictCols;
    /* WHERE for ON CONFLICT DO SELECT/UPDATE */
    Node       *onConflictWhere;
    /* FOR PORTION OF clause for UPDATE/DELETE */
    Node       *forPortionOf;
    /* RTI of the EXCLUDED pseudo relation */
    Index       exclRelRTI;
    /* tlist of the EXCLUDED pseudo relation */
    List       *exclRelTlist;
    /* per-target-table lists of actions for MERGE */
    List       *mergeActionLists;
    /* per-target-table join conditions for MERGE */
    List       *mergeJoinConditions;
} ModifyTable;
 
struct PartitionPruneInfo;      /* forward reference to struct below */
 
/* ----------------
 *   Append node -
 *      Generate the concatenation of the results of sub-plans.
 * ----------------
 */
typedef struct Append
{
    Plan        plan;
 
    /* RTIs of appendrel(s) formed by this node */
    Bitmapset  *apprelids;
 
    /* sets of RTIs of appendrels consolidated into this node */
    List       *child_append_relid_sets;
 
    /* plans to run */
    List       *appendplans;
 
    /* # of asynchronous plans */
    int         nasyncplans;
 
    /*
     * All 'appendplans' preceding this index are non-partial plans. All
     * 'appendplans' from this index onwards are partial plans.
     */
    int         first_partial_plan;
 
    /*
     * Index into PlannedStmt.partPruneInfos and parallel lists in EState:
     * es_part_prune_states and es_part_prune_results. Set to -1 if no
     * run-time pruning is used.
     */
    int         part_prune_index;
} Append;
 
/* ----------------
 *   MergeAppend node -
 *      Merge the results of pre-sorted sub-plans to preserve the ordering.
 * ----------------
 */
typedef struct MergeAppend
{
    Plan        plan;
 
    /* RTIs of appendrel(s) formed by this node */
    Bitmapset  *apprelids;
 
    /* sets of RTIs of appendrels consolidated into this node */
    List       *child_append_relid_sets;
 
    /* plans to run */
    List       *mergeplans;
 
    /* these fields are just like the sort-key info in struct Sort: */
 
    /* number of sort-key columns */
    int         numCols;
 
    /* their indexes in the target list */
    AttrNumber *sortColIdx pg_node_attr(array_size(numCols));
 
    /* OIDs of operators to sort them by */
    Oid        *sortOperators pg_node_attr(array_size(numCols));
 
    /* OIDs of collations */
    Oid        *collations pg_node_attr(array_size(numCols));
 
    /* NULLS FIRST/LAST directions */
    bool       *nullsFirst pg_node_attr(array_size(numCols));
 
    /*
     * Index into PlannedStmt.partPruneInfos and parallel lists in EState:
     * es_part_prune_states and es_part_prune_results. Set to -1 if no
     * run-time pruning is used.
     */
    int         part_prune_index;
} MergeAppend;
 
/* ----------------
 *  RecursiveUnion node -
 *      Generate a recursive union of two subplans.
 *
 * The "outer" subplan is always the non-recursive term, and the "inner"
 * subplan is the recursive term.
 * ----------------
 */
typedef struct RecursiveUnion
{
    Plan        plan;
 
    /* ID of Param representing work table */
    int         wtParam;
 
    /* Remaining fields are zero/null in UNION ALL case */
 
    /* number of columns to check for duplicate-ness */
    int         numCols;
 
    /* their indexes in the target list */
    AttrNumber *dupColIdx pg_node_attr(array_size(numCols));
 
    /* equality operators to compare with */
    Oid        *dupOperators pg_node_attr(array_size(numCols));
    Oid        *dupCollations pg_node_attr(array_size(numCols));
 
    /* estimated number of groups in input */
    Cardinality numGroups;
} RecursiveUnion;
 
/* ----------------
 *   BitmapAnd node -
 *      Generate the intersection of the results of sub-plans.
 *
 * The subplans must be of types that yield tuple bitmaps.  The targetlist
 * and qual fields of the plan are unused and are always NIL.
 * ----------------
 */
typedef struct BitmapAnd
{
    Plan        plan;
    List       *bitmapplans;
} BitmapAnd;
 
/* ----------------
 *   BitmapOr node -
 *      Generate the union of the results of sub-plans.
 *
 * The subplans must be of types that yield tuple bitmaps.  The targetlist
 * and qual fields of the plan are unused and are always NIL.
 * ----------------
 */
typedef struct BitmapOr
{
    Plan        plan;
    bool        isshared;
    List       *bitmapplans;
} BitmapOr;
 
/*
 * ==========
 * Scan nodes
 *
 * Scan is an abstract type that all relation scan plan types inherit from.
 * ==========
 */
typedef struct Scan
{
    pg_node_attr(abstract)
 
    Plan        plan;
    /* relid is index into the range table */
    Index       scanrelid;
} Scan;
 
/* ----------------
 *      sequential scan node
 * ----------------
 */
typedef struct SeqScan
{
    Scan        scan;
} SeqScan;
 
/* ----------------
 *      table sample scan node
 * ----------------
 */
typedef struct SampleScan
{
    Scan        scan;
    /* use struct pointer to avoid including parsenodes.h here */
    struct TableSampleClause *tablesample;
} SampleScan;
 
/* ----------------
 *      index scan node
 *
 * indexqualorig is an implicitly-ANDed list of index qual expressions, each
 * in the same form it appeared in the query WHERE condition.  Each should
 * be of the form (indexkey OP comparisonval) or (comparisonval OP indexkey).
 * The indexkey is a Var or expression referencing column(s) of the index's
 * base table.  The comparisonval might be any expression, but it won't use
 * any columns of the base table.  The expressions are ordered by index
 * column position (but items referencing the same index column can appear
 * in any order).  indexqualorig is used at runtime only if we have to recheck
 * a lossy indexqual.
 *
 * indexqual has the same form, but the expressions have been commuted if
 * necessary to put the indexkeys on the left, and the indexkeys are replaced
 * by Var nodes identifying the index columns (their varno is INDEX_VAR and
 * their varattno is the index column number).
 *
 * indexorderbyorig is similarly the original form of any ORDER BY expressions
 * that are being implemented by the index, while indexorderby is modified to
 * have index column Vars on the left-hand side.  Here, multiple expressions
 * must appear in exactly the ORDER BY order, and this is not necessarily the
 * index column order.  Only the expressions are provided, not the auxiliary
 * sort-order information from the ORDER BY SortGroupClauses; it's assumed
 * that the sort ordering is fully determinable from the top-level operators.
 * indexorderbyorig is used at runtime to recheck the ordering, if the index
 * cannot calculate an accurate ordering.  It is also needed for EXPLAIN.
 *
 * indexorderbyops is a list of the OIDs of the operators used to sort the
 * ORDER BY expressions.  This is used together with indexorderbyorig to
 * recheck ordering at run time.  (Note that indexorderby, indexorderbyorig,
 * and indexorderbyops are used for amcanorderbyop cases, not amcanorder.)
 *
 * indexorderdir specifies the scan ordering, for indexscans on amcanorder
 * indexes (for other indexes it should be "don't care").
 * ----------------
 */
typedef struct IndexScan
{
    Scan        scan;
    /* OID of index to scan */
    Oid         indexid;
    /* list of index quals (usually OpExprs) */
    List       *indexqual;
    /* the same in original form */
    List       *indexqualorig;
    /* list of index ORDER BY exprs */
    List       *indexorderby;
    /* the same in original form */
    List       *indexorderbyorig;
    /* OIDs of sort ops for ORDER BY exprs */
    List       *indexorderbyops;
    /* forward or backward or don't care */
    ScanDirection indexorderdir;
} IndexScan;
 
/* ----------------
 *      index-only scan node
 *
 * IndexOnlyScan is very similar to IndexScan, but it specifies an
 * index-only scan, in which the data comes from the index not the heap.
 * Because of this, *all* Vars in the plan node's targetlist, qual, and
 * index expressions reference index columns and have varno = INDEX_VAR.
 *
 * We could almost use indexqual directly against the index's output tuple
 * when rechecking lossy index operators, but that won't work for quals on
 * index columns that are not retrievable.  Hence, recheckqual is needed
 * for rechecks: it expresses the same condition as indexqual, but using
 * only index columns that are retrievable.  (We will not generate an
 * index-only scan if this is not possible.  An example is that if an
 * index has table column "x" in a retrievable index column "ind1", plus
 * an expression f(x) in a non-retrievable column "ind2", an indexable
 * query on f(x) will use "ind2" in indexqual and f(ind1) in recheckqual.
 * Without the "ind1" column, an index-only scan would be disallowed.)
 *
 * We don't currently need a recheckable equivalent of indexorderby,
 * because we don't support lossy operators in index ORDER BY.
 *
 * To help EXPLAIN interpret the index Vars for display, we provide
 * indextlist, which represents the contents of the index as a targetlist
 * with one TLE per index column.  Vars appearing in this list reference
 * the base table, and this is the only field in the plan node that may
 * contain such Vars.  Also, for the convenience of setrefs.c, TLEs in
 * indextlist are marked as resjunk if they correspond to columns that
 * the index AM cannot reconstruct.
 * ----------------
 */
typedef struct IndexOnlyScan
{
    Scan        scan;
    /* OID of index to scan */
    Oid         indexid;
    /* list of index quals (usually OpExprs) */
    List       *indexqual;
    /* index quals in recheckable form */
    List       *recheckqual;
    /* list of index ORDER BY exprs */
    List       *indexorderby;
    /* TargetEntry list describing index's cols */
    List       *indextlist;
    /* forward or backward or don't care */
    ScanDirection indexorderdir;
} IndexOnlyScan;
 
/* ----------------
 *      bitmap index scan node
 *
 * BitmapIndexScan delivers a bitmap of potential tuple locations;
 * it does not access the heap itself.  The bitmap is used by an
 * ancestor BitmapHeapScan node, possibly after passing through
 * intermediate BitmapAnd and/or BitmapOr nodes to combine it with
 * the results of other BitmapIndexScans.
 *
 * The fields have the same meanings as for IndexScan, except we don't
 * store a direction flag because direction is uninteresting.
 *
 * In a BitmapIndexScan plan node, the targetlist and qual fields are
 * not used and are always NIL.  The indexqualorig field is unused at
 * run time too, but is saved for the benefit of EXPLAIN.
 * ----------------
 */
typedef struct BitmapIndexScan
{
    Scan        scan;
    /* OID of index to scan */
    Oid         indexid;
    /* Create shared bitmap if set */
    bool        isshared;
    /* list of index quals (OpExprs) */
    List       *indexqual;
    /* the same in original form */
    List       *indexqualorig;
} BitmapIndexScan;
 
/* ----------------
 *      bitmap sequential scan node
 *
 * This needs a copy of the qual conditions being used by the input index
 * scans because there are various cases where we need to recheck the quals;
 * for example, when the bitmap is lossy about the specific rows on a page
 * that meet the index condition.
 * ----------------
 */
typedef struct BitmapHeapScan
{
    Scan        scan;
    /* index quals, in standard expr form */
    List       *bitmapqualorig;
} BitmapHeapScan;
 
/* ----------------
 *      tid scan node
 *
 * tidquals is an implicitly OR'ed list of qual expressions of the form
 * "CTID = pseudoconstant", or "CTID = ANY(pseudoconstant_array)",
 * or a CurrentOfExpr for the relation.
 * ----------------
 */
typedef struct TidScan
{
    Scan        scan;
    /* qual(s) involving CTID = something */
    List       *tidquals;
} TidScan;
 
/* ----------------
 *      tid range scan node
 *
 * tidrangequals is an implicitly AND'ed list of qual expressions of the form
 * "CTID relop pseudoconstant", where relop is one of >,>=,<,<=.
 * ----------------
 */
typedef struct TidRangeScan
{
    Scan        scan;
    /* qual(s) involving CTID op something */
    List       *tidrangequals;
} TidRangeScan;
 
/* ----------------
 *      subquery scan node
 *
 * SubqueryScan is for scanning the output of a sub-query in the range table.
 * We often need an extra plan node above the sub-query's plan to perform
 * expression evaluations (which we can't push into the sub-query without
 * risking changing its semantics).  Although we are not scanning a physical
 * relation, we make this a descendant of Scan anyway for code-sharing
 * purposes.
 *
 * SubqueryScanStatus caches the trivial_subqueryscan property of the node.
 * SUBQUERY_SCAN_UNKNOWN means not yet determined.  This is only used during
 * planning.
 *
 * Note: we store the sub-plan in the type-specific subplan field, not in
 * the generic lefttree field as you might expect.  This is because we do
 * not want plan-tree-traversal routines to recurse into the subplan without
 * knowing that they are changing Query contexts.
 * ----------------
 */
typedef enum SubqueryScanStatus
{
    SUBQUERY_SCAN_UNKNOWN,
    SUBQUERY_SCAN_TRIVIAL,
    SUBQUERY_SCAN_NONTRIVIAL,
} SubqueryScanStatus;
 
typedef struct SubqueryScan
{
    Scan        scan;
    Plan       *subplan;
    SubqueryScanStatus scanstatus;
} SubqueryScan;
 
/* ----------------
 *      FunctionScan node
 * ----------------
 */
typedef struct FunctionScan
{
    Scan        scan;
    /* list of RangeTblFunction nodes */
    List       *functions;
    /* WITH ORDINALITY */
    bool        funcordinality;
} FunctionScan;
 
/* ----------------
 *      ValuesScan node
 * ----------------
 */
typedef struct ValuesScan
{
    Scan        scan;
    /* list of expression lists */
    List       *values_lists;
} ValuesScan;
 
/* ----------------
 *      TableFunc scan node
 * ----------------
 */
typedef struct TableFuncScan
{
    Scan        scan;
    /* table function node */
    TableFunc  *tablefunc;
} TableFuncScan;
 
/* ----------------
 *      CteScan node
 * ----------------
 */
typedef struct CteScan
{
    Scan        scan;
    /* ID of init SubPlan for CTE */
    int         ctePlanId;
    /* ID of Param representing CTE output */
    int         cteParam;
} CteScan;
 
/* ----------------
 *      NamedTuplestoreScan node
 * ----------------
 */
typedef struct NamedTuplestoreScan
{
    Scan        scan;
    /* Name given to Ephemeral Named Relation */
    char       *enrname;
} NamedTuplestoreScan;
 
/* ----------------
 *      WorkTableScan node
 * ----------------
 */
typedef struct WorkTableScan
{
    Scan        scan;
    /* ID of Param representing work table */
    int         wtParam;
} WorkTableScan;
 
/* ----------------
 *      ForeignScan node
 *
 * fdw_exprs and fdw_private are both under the control of the foreign-data
 * wrapper, but fdw_exprs is presumed to contain expression trees and will
 * be post-processed accordingly by the planner; fdw_private won't be.
 * Note that everything in both lists must be copiable by copyObject().
 * One way to store an arbitrary blob of bytes is to represent it as a bytea
 * Const.  Usually, though, you'll be better off choosing a representation
 * that can be dumped usefully by nodeToString().
 *
 * fdw_scan_tlist is a targetlist describing the contents of the scan tuple
 * returned by the FDW; it can be NIL if the scan tuple matches the declared
 * rowtype of the foreign table, which is the normal case for a simple foreign
 * table scan.  (If the plan node represents a foreign join, fdw_scan_tlist
 * is required since there is no rowtype available from the system catalogs.)
 * When fdw_scan_tlist is provided, Vars in the node's tlist and quals must
 * have varno INDEX_VAR, and their varattnos correspond to resnos in the
 * fdw_scan_tlist (which are also column numbers in the actual scan tuple).
 * fdw_scan_tlist is never actually executed; it just holds expression trees
 * describing what is in the scan tuple's columns.
 *
 * fdw_recheck_quals should contain any quals which the core system passed to
 * the FDW but which were not added to scan.plan.qual; that is, it should
 * contain the quals being checked remotely.  This is needed for correct
 * behavior during EvalPlanQual rechecks.
 *
 * When the plan node represents a foreign join, scan.scanrelid is zero and
 * fs_relids must be consulted to identify the join relation.  (fs_relids
 * is valid for simple scans as well, but will always match scan.scanrelid.)
 * fs_relids includes outer joins; fs_base_relids does not.
 *
 * If the FDW's PlanDirectModify() callback decides to repurpose a ForeignScan
 * node to perform the UPDATE or DELETE operation directly in the remote
 * server, it sets 'operation' and 'resultRelation' to identify the operation
 * type and target relation.  Note that these fields are only set if the
 * modification is performed *fully* remotely; otherwise, the modification is
 * driven by a local ModifyTable node and 'operation' is left to CMD_SELECT.
 * ----------------
 */
typedef struct ForeignScan
{
    Scan        scan;
    /* SELECT/INSERT/UPDATE/DELETE */
    CmdType     operation;
    /* direct modification target's RT index */
    Index       resultRelation;
    /* user to perform the scan as; 0 means to check as current user */
    Oid         checkAsUser;
    /* OID of foreign server */
    Oid         fs_server;
    /* expressions that FDW may evaluate */
    List       *fdw_exprs;
    /* private data for FDW */
    List       *fdw_private;
    /* optional tlist describing scan tuple */
    List       *fdw_scan_tlist;
    /* original quals not in scan.plan.qual */
    List       *fdw_recheck_quals;
    /* base+OJ RTIs generated by this scan */
    Bitmapset  *fs_relids;
    /* base RTIs generated by this scan */
    Bitmapset  *fs_base_relids;
    /* true if any "system column" is needed */
    bool        fsSystemCol;
} ForeignScan;
 
/* ----------------
 *     CustomScan node
 *
 * The comments for ForeignScan's fdw_exprs, fdw_private, fdw_scan_tlist,
 * and fs_relids fields apply equally to CustomScan's custom_exprs,
 * custom_private, custom_scan_tlist, and custom_relids fields.  The
 * convention of setting scan.scanrelid to zero for joins applies as well.
 *
 * Note that since Plan trees can be copied, custom scan providers *must*
 * fit all plan data they need into those fields; embedding CustomScan in
 * a larger struct will not work.
 * ----------------
 */
struct CustomScanMethods;
 
typedef struct CustomScan
{
    Scan        scan;
    /* mask of CUSTOMPATH_* flags, see nodes/extensible.h */
    uint32      flags;
    /* list of Plan nodes, if any */
    List       *custom_plans;
    /* expressions that custom code may evaluate */
    List       *custom_exprs;
    /* private data for custom code */
    List       *custom_private;
    /* optional tlist describing scan tuple */
    List       *custom_scan_tlist;
    /* RTIs generated by this scan */
    Bitmapset  *custom_relids;
 
    /*
     * NOTE: The method field of CustomScan is required to be a pointer to a
     * static table of callback functions.  So we don't copy the table itself,
     * just reference the original one.
     */
    const struct CustomScanMethods *methods;
} CustomScan;
 
/*
 * ==========
 * Join nodes
 * ==========
 */
 
/* ----------------
 *      Join node
 *
 * jointype:    rule for joining tuples from left and right subtrees
 * inner_unique each outer tuple can match to no more than one inner tuple
 * joinqual:    qual conditions that came from JOIN/ON or JOIN/USING
 *              (plan.qual contains conditions that came from WHERE)
 *
 * When jointype is INNER, joinqual and plan.qual are semantically
 * interchangeable.  For OUTER jointypes, the two are *not* interchangeable;
 * only joinqual is used to determine whether a match has been found for
 * the purpose of deciding whether to generate null-extended tuples.
 * (But plan.qual is still applied before actually returning a tuple.)
 * For an outer join, only joinquals are allowed to be used as the merge
 * or hash condition of a merge or hash join.
 *
 * inner_unique is set if the joinquals are such that no more than one inner
 * tuple could match any given outer tuple.  This allows the executor to
 * skip searching for additional matches.  (This must be provable from just
 * the joinquals, ignoring plan.qual, due to where the executor tests it.)
 * ----------------
 */
typedef struct Join
{
    pg_node_attr(abstract)
 
    Plan        plan;
    JoinType    jointype;
    bool        inner_unique;
    /* JOIN quals (in addition to plan.qual) */
    List       *joinqual;
} Join;
 
/* ----------------
 *      nest loop join node
 *
 * The nestParams list identifies any executor Params that must be passed
 * into execution of the inner subplan carrying values from the current row
 * of the outer subplan.  Currently we restrict these values to be simple
 * Vars, but perhaps someday that'd be worth relaxing.  (Note: during plan
 * creation, the paramval can actually be a PlaceHolderVar expression; but it
 * must be a Var with varno OUTER_VAR by the time it gets to the executor.)
 * ----------------
 */
typedef struct NestLoop
{
    Join        join;
    /* list of NestLoopParam nodes */
    List       *nestParams;
} NestLoop;
 
typedef struct NestLoopParam
{
    pg_node_attr(no_equal, no_query_jumble)
 
    NodeTag     type;
    /* number of the PARAM_EXEC Param to set */
    int         paramno;
    /* outer-relation Var to assign to Param */
    Var        *paramval;
} NestLoopParam;
 
/* ----------------
 *      merge join node
 *
 * The expected ordering of each mergeable column is described by a btree
 * opfamily OID, a collation OID, a direction (BTLessStrategyNumber or
 * BTGreaterStrategyNumber) and a nulls-first flag.  Note that the two sides
 * of each mergeclause may be of different datatypes, but they are ordered the
 * same way according to the common opfamily and collation.  The operator in
 * each mergeclause must be an equality operator of the indicated opfamily.
 * ----------------
 */
typedef struct MergeJoin
{
    Join        join;
 
    /* Can we skip mark/restore calls? */
    bool        skip_mark_restore;
 
    /* mergeclauses as expression trees */
    List       *mergeclauses;
 
    /* these are arrays, but have the same length as the mergeclauses list: */
 
    /* per-clause OIDs of btree opfamilies */
    Oid        *mergeFamilies pg_node_attr(array_size(mergeclauses));
 
    /* per-clause OIDs of collations */
    Oid        *mergeCollations pg_node_attr(array_size(mergeclauses));
 
    /* per-clause ordering (ASC or DESC) */
    bool       *mergeReversals pg_node_attr(array_size(mergeclauses));
 
    /* per-clause nulls ordering */
    bool       *mergeNullsFirst pg_node_attr(array_size(mergeclauses));
} MergeJoin;
 
/* ----------------
 *      hash join node
 * ----------------
 */
typedef struct HashJoin
{
    Join        join;
    List       *hashclauses;
    List       *hashoperators;
    List       *hashcollations;
 
    /*
     * List of expressions to be hashed for tuples from the outer plan, to
     * perform lookups in the hashtable over the inner plan.
     */
    List       *hashkeys;
} HashJoin;
 
/* ----------------
 *      materialization node
 * ----------------
 */
typedef struct Material
{
    Plan        plan;
} Material;
 
/* ----------------
 *      memoize node
 * ----------------
 */
typedef struct Memoize
{
    Plan        plan;
 
    /* size of the two arrays below */
    int         numKeys;
 
    /* hash operators for each key */
    Oid        *hashOperators pg_node_attr(array_size(numKeys));
 
    /* collations for each key */
    Oid        *collations pg_node_attr(array_size(numKeys));
 
    /* cache keys in the form of exprs containing parameters */
    List       *param_exprs;
 
    /*
     * true if the cache entry should be marked as complete after we store the
     * first tuple in it.
     */
    bool        singlerow;
 
    /*
     * true when cache key should be compared bit by bit, false when using
     * hash equality ops
     */
    bool        binary_mode;
 
    /*
     * The maximum number of entries that the planner expects will fit in the
     * cache, or 0 if unknown
     */
    uint32      est_entries;
 
    /* paramids from param_exprs */
    Bitmapset  *keyparamids;
 
    /* Estimated number of rescans, for EXPLAIN */
    Cardinality est_calls;
 
    /* Estimated number of distinct lookup keys, for EXPLAIN */
    Cardinality est_unique_keys;
 
    /* Estimated cache hit ratio, for EXPLAIN */
    double      est_hit_ratio;
 
} Memoize;
 
/* ----------------
 *      sort node
 * ----------------
 */
typedef struct Sort
{
    Plan        plan;
 
    /* number of sort-key columns */
    int         numCols;
 
    /* their indexes in the target list */
    AttrNumber *sortColIdx pg_node_attr(array_size(numCols));
 
    /* OIDs of operators to sort them by */
    Oid        *sortOperators pg_node_attr(array_size(numCols));
 
    /* OIDs of collations */
    Oid        *collations pg_node_attr(array_size(numCols));
 
    /* NULLS FIRST/LAST directions */
    bool       *nullsFirst pg_node_attr(array_size(numCols));
} Sort;
 
/* ----------------
 *      incremental sort node
 * ----------------
 */
typedef struct IncrementalSort
{
    Sort        sort;
    /* number of presorted columns */
    int         nPresortedCols;
} IncrementalSort;
 
/* ---------------
 *   group node -
 *      Used for queries with GROUP BY (but no aggregates) specified.
 *      The input must be presorted according to the grouping columns.
 * ---------------
 */
typedef struct Group
{
    Plan        plan;
 
    /* number of grouping columns */
    int         numCols;
 
    /* their indexes in the target list */
    AttrNumber *grpColIdx pg_node_attr(array_size(numCols));
 
    /* equality operators to compare with */
    Oid        *grpOperators pg_node_attr(array_size(numCols));
    Oid        *grpCollations pg_node_attr(array_size(numCols));
} Group;
 
/* ---------------
 *      aggregate node
 *
 * An Agg node implements plain or grouped aggregation.  For grouped
 * aggregation, we can work with presorted input or unsorted input;
 * the latter strategy uses an internal hashtable.
 *
 * Notice the lack of any direct info about the aggregate functions to be
 * computed.  They are found by scanning the node's tlist and quals during
 * executor startup.  (It is possible that there are no aggregate functions;
 * this could happen if they get optimized away by constant-folding, or if
 * we are using the Agg node to implement hash-based grouping.)
 * ---------------
 */
typedef struct Agg
{
    Plan        plan;
 
    /* basic strategy, see nodes.h */
    AggStrategy aggstrategy;
 
    /* agg-splitting mode, see nodes.h */
    AggSplit    aggsplit;
 
    /* number of grouping columns */
    int         numCols;
 
    /* their indexes in the target list */
    AttrNumber *grpColIdx pg_node_attr(array_size(numCols));
 
    /* equality operators to compare with */
    Oid        *grpOperators pg_node_attr(array_size(numCols));
    Oid        *grpCollations pg_node_attr(array_size(numCols));
 
    /* estimated number of groups in input */
    Cardinality numGroups;
 
    /* for pass-by-ref transition data */
    uint64      transitionSpace;
 
    /* IDs of Params used in Aggref inputs */
    Bitmapset  *aggParams;
 
    /* Note: planner provides numGroups & aggParams only in HASHED/MIXED case */
 
    /* grouping sets to use */
    List       *groupingSets;
 
    /* chained Agg/Sort nodes */
    List       *chain;
} Agg;
 
/* ----------------
 *      window aggregate node
 * ----------------
 */
typedef struct WindowAgg
{
    Plan        plan;
 
    /* name of WindowClause implemented by this node */
    char       *winname;
 
    /* ID referenced by window functions */
    Index       winref;
 
    /* number of columns in partition clause */
    int         partNumCols;
 
    /* their indexes in the target list */
    AttrNumber *partColIdx pg_node_attr(array_size(partNumCols));
 
    /* equality operators for partition columns */
    Oid        *partOperators pg_node_attr(array_size(partNumCols));
 
    /* collations for partition columns */
    Oid        *partCollations pg_node_attr(array_size(partNumCols));
 
    /* number of columns in ordering clause */
    int         ordNumCols;
 
    /* their indexes in the target list */
    AttrNumber *ordColIdx pg_node_attr(array_size(ordNumCols));
 
    /* equality operators for ordering columns */
    Oid        *ordOperators pg_node_attr(array_size(ordNumCols));
 
    /* collations for ordering columns */
    Oid        *ordCollations pg_node_attr(array_size(ordNumCols));
 
    /* frame_clause options, see WindowDef */
    int         frameOptions;
 
    /* expression for starting bound, if any */
    Node       *startOffset;
 
    /* expression for ending bound, if any */
    Node       *endOffset;
 
    /* qual to help short-circuit execution */
    List       *runCondition;
 
    /* runCondition for display in EXPLAIN */
    List       *runConditionOrig;
 
    /* these fields are used with RANGE offset PRECEDING/FOLLOWING: */
 
    /* in_range function for startOffset */
    Oid         startInRangeFunc;
 
    /* in_range function for endOffset */
    Oid         endInRangeFunc;
 
    /* collation for in_range tests */
    Oid         inRangeColl;
 
    /* use ASC sort order for in_range tests? */
    bool        inRangeAsc;
 
    /* nulls sort first for in_range tests? */
    bool        inRangeNullsFirst;
 
    /*
     * false for all apart from the WindowAgg that's closest to the root of
     * the plan
     */
    bool        topWindow;
} WindowAgg;
 
/* ----------------
 *      unique node
 * ----------------
 */
typedef struct Unique
{
    Plan        plan;
 
    /* number of columns to check for uniqueness */
    int         numCols;
 
    /* their indexes in the target list */
    AttrNumber *uniqColIdx pg_node_attr(array_size(numCols));
 
    /* equality operators to compare with */
    Oid        *uniqOperators pg_node_attr(array_size(numCols));
 
    /* collations for equality comparisons */
    Oid        *uniqCollations pg_node_attr(array_size(numCols));
} Unique;
 
/* ------------
 *      gather node
 *
 * Note: rescan_param is the ID of a PARAM_EXEC parameter slot.  That slot
 * will never actually contain a value, but the Gather node must flag it as
 * having changed whenever it is rescanned.  The child parallel-aware scan
 * nodes are marked as depending on that parameter, so that the rescan
 * machinery is aware that their output is likely to change across rescans.
 * In some cases we don't need a rescan Param, so rescan_param is set to -1.
 * ------------
 */
typedef struct Gather
{
    Plan        plan;
    /* planned number of worker processes */
    int         num_workers;
    /* ID of Param that signals a rescan, or -1 */
    int         rescan_param;
    /* don't execute plan more than once */
    bool        single_copy;
    /* suppress EXPLAIN display (for testing)? */
    bool        invisible;
 
    /*
     * param id's of initplans which are referred at gather or one of its
     * child nodes
     */
    Bitmapset  *initParam;
} Gather;
 
/* ------------
 *      gather merge node
 * ------------
 */
typedef struct GatherMerge
{
    Plan        plan;
 
    /* planned number of worker processes */
    int         num_workers;
 
    /* ID of Param that signals a rescan, or -1 */
    int         rescan_param;
 
    /* remaining fields are just like the sort-key info in struct Sort */
 
    /* number of sort-key columns */
    int         numCols;
 
    /* their indexes in the target list */
    AttrNumber *sortColIdx pg_node_attr(array_size(numCols));
 
    /* OIDs of operators to sort them by */
    Oid        *sortOperators pg_node_attr(array_size(numCols));
 
    /* OIDs of collations */
    Oid        *collations pg_node_attr(array_size(numCols));
 
    /* NULLS FIRST/LAST directions */
    bool       *nullsFirst pg_node_attr(array_size(numCols));
 
    /*
     * param id's of initplans which are referred at gather merge or one of
     * its child nodes
     */
    Bitmapset  *initParam;
} GatherMerge;
 
/* ----------------
 *      hash build node
 *
 * If the executor is supposed to try to apply skew join optimization, then
 * skewTable/skewColumn/skewInherit identify the outer relation's join key
 * column, from which the relevant MCV statistics can be fetched.
 * ----------------
 */
typedef struct Hash
{
    Plan        plan;
 
    /*
     * List of expressions to be hashed for tuples from Hash's outer plan,
     * needed to put them into the hashtable.
     */
    /* hash keys for the hashjoin condition */
    List       *hashkeys;
    /* outer join key's table OID, or InvalidOid */
    Oid         skewTable;
    /* outer join key's column #, or zero */
    AttrNumber  skewColumn;
    /* is outer join rel an inheritance tree? */
    bool        skewInherit;
    /* all other info is in the parent HashJoin node */
    /* estimate total rows if parallel_aware */
    Cardinality rows_total;
} Hash;
 
/* ----------------
 *      setop node
 * ----------------
 */
typedef struct SetOp
{
    Plan        plan;
 
    /* what to do, see nodes.h */
    SetOpCmd    cmd;
 
    /* how to do it, see nodes.h */
    SetOpStrategy strategy;
 
    /* number of columns to compare */
    int         numCols;
 
    /* their indexes in the target list */
    AttrNumber *cmpColIdx pg_node_attr(array_size(numCols));
 
    /* comparison operators (either equality operators or sort operators) */
    Oid        *cmpOperators pg_node_attr(array_size(numCols));
    Oid        *cmpCollations pg_node_attr(array_size(numCols));
 
    /* nulls-first flags if sorting, otherwise not interesting */
    bool       *cmpNullsFirst pg_node_attr(array_size(numCols));
 
    /* estimated number of groups in left input */
    Cardinality numGroups;
} SetOp;
 
/* ----------------
 *      lock-rows node
 *
 * rowMarks identifies the rels to be locked by this node; it should be
 * a subset of the rowMarks listed in the top-level PlannedStmt.
 * epqParam is a Param that all scan nodes below this one must depend on.
 * It is used to force re-evaluation of the plan during EvalPlanQual.
 * ----------------
 */
typedef struct LockRows
{
    Plan        plan;
    /* a list of PlanRowMark's */
    List       *rowMarks;
    /* ID of Param for EvalPlanQual re-eval */
    int         epqParam;
} LockRows;
 
/* ----------------
 *      limit node
 *
 * Note: as of Postgres 8.2, the offset and count expressions are expected
 * to yield int8, rather than int4 as before.
 * ----------------
 */
typedef struct Limit
{
    Plan        plan;
 
    /* OFFSET parameter, or NULL if none */
    Node       *limitOffset;
 
    /* COUNT parameter, or NULL if none */
    Node       *limitCount;
 
    /* limit type */
    LimitOption limitOption;
 
    /* number of columns to check for similarity  */
    int         uniqNumCols;
 
    /* their indexes in the target list */
    AttrNumber *uniqColIdx pg_node_attr(array_size(uniqNumCols));
 
    /* equality operators to compare with */
    Oid        *uniqOperators pg_node_attr(array_size(uniqNumCols));
 
    /* collations for equality comparisons */
    Oid        *uniqCollations pg_node_attr(array_size(uniqNumCols));
} Limit;
 
 
/*
 * RowMarkType -
 *    enums for types of row-marking operations
 *
 * The first four of these values represent different lock strengths that
 * we can take on tuples according to SELECT FOR [KEY] UPDATE/SHARE requests.
 * We support these on regular tables, as well as on foreign tables whose FDWs
 * report support for late locking.  For other foreign tables, any locking
 * that might be done for such requests must happen during the initial row
 * fetch; their FDWs provide no mechanism for going back to lock a row later.
 * This means that the semantics will be a bit different than for a local
 * table; in particular we are likely to lock more rows than would be locked
 * locally, since remote rows will be locked even if they then fail
 * locally-checked restriction or join quals.  However, the prospect of
 * doing a separate remote query to lock each selected row is usually pretty
 * unappealing, so early locking remains a credible design choice for FDWs.
 *
 * When doing UPDATE/DELETE/MERGE/SELECT FOR UPDATE/SHARE, we have to uniquely
 * identify all the source rows, not only those from the target relations, so
 * that we can perform EvalPlanQual rechecking at need.  For plain tables we
 * can just fetch the TID, much as for a target relation; this case is
 * represented by ROW_MARK_REFERENCE.  Otherwise (for example for VALUES or
 * FUNCTION scans) we have to copy the whole row value.  ROW_MARK_COPY is
 * pretty inefficient, since most of the time we'll never need the data; but
 * fortunately the overhead is usually not performance-critical in practice.
 * By default we use ROW_MARK_COPY for foreign tables, but if the FDW has
 * a concept of rowid it can request to use ROW_MARK_REFERENCE instead.
 * (Again, this probably doesn't make sense if a physical remote fetch is
 * needed, but for FDWs that map to local storage it might be credible.)
 */
typedef enum RowMarkType
{
    ROW_MARK_EXCLUSIVE,         /* obtain exclusive tuple lock */
    ROW_MARK_NOKEYEXCLUSIVE,    /* obtain no-key exclusive tuple lock */
    ROW_MARK_SHARE,             /* obtain shared tuple lock */
    ROW_MARK_KEYSHARE,          /* obtain keyshare tuple lock */
    ROW_MARK_REFERENCE,         /* just fetch the TID, don't lock it */
    ROW_MARK_COPY,              /* physically copy the row value */
} RowMarkType;
 
#define RowMarkRequiresRowShareLock(marktype)  ((marktype) <= ROW_MARK_KEYSHARE)
 
/*
 * PlanRowMark -
 *     plan-time representation of FOR [KEY] UPDATE/SHARE clauses
 *
 * When doing UPDATE/DELETE/MERGE/SELECT FOR UPDATE/SHARE, we create a separate
 * PlanRowMark node for each non-target relation in the query.  Relations that
 * are not specified as FOR UPDATE/SHARE are marked ROW_MARK_REFERENCE (if
 * regular tables or supported foreign tables) or ROW_MARK_COPY (if not).
 *
 * Initially all PlanRowMarks have rti == prti and isParent == false.
 * When the planner discovers that a relation is the root of an inheritance
 * tree, it sets isParent true, and adds an additional PlanRowMark to the
 * list for each child relation (including the target rel itself in its role
 * as a child, if it is not a partitioned table).  Any non-leaf partitioned
 * child relations will also have entries with isParent = true.  The child
 * entries have rti == child rel's RT index and prti == top parent's RT index,
 * and can therefore be recognized as children by the fact that prti != rti.
 * The parent's allMarkTypes field gets the OR of (1<<markType) across all
 * its children (this definition allows children to use different markTypes).
 *
 * The planner also adds resjunk output columns to the plan that carry
 * information sufficient to identify the locked or fetched rows.  When
 * markType != ROW_MARK_COPY, these columns are named
 *      tableoid%u          OID of table
 *      ctid%u              TID of row
 * The tableoid column is only present for an inheritance hierarchy.
 * When markType == ROW_MARK_COPY, there is instead a single column named
 *      wholerow%u          whole-row value of relation
 * (An inheritance hierarchy could have all three resjunk output columns,
 * if some children use a different markType than others.)
 * In all three cases, %u represents the rowmark ID number (rowmarkId).
 * This number is unique within a plan tree, except that child relation
 * entries copy their parent's rowmarkId.  (Assigning unique numbers
 * means we needn't renumber rowmarkIds when flattening subqueries, which
 * would require finding and renaming the resjunk columns as well.)
 * Note this means that all tables in an inheritance hierarchy share the
 * same resjunk column names.
 */
typedef struct PlanRowMark
{
    pg_node_attr(no_equal, no_query_jumble)
 
    NodeTag     type;
    /* range table index of markable relation */
    Index       rti;
    /* range table index of parent relation */
    Index       prti;
    /* unique identifier for resjunk columns */
    Index       rowmarkId;
    /* see enum above */
    RowMarkType markType;
    /* OR of (1<<markType) for all children */
    int         allMarkTypes;
    /* LockingClause's strength, or LCS_NONE */
    LockClauseStrength strength;
    /* NOWAIT and SKIP LOCKED options */
    LockWaitPolicy waitPolicy;
    /* true if this is a "dummy" parent entry */
    bool        isParent;
} PlanRowMark;
 
 
/*
 * Node types to represent partition pruning information.
 */
 
/*
 * PartitionPruneInfo - Details required to allow the executor to prune
 * partitions.
 *
 * Here we store mapping details to allow translation of a partitioned table's
 * index as returned by the partition pruning code into subplan indexes for
 * plan types which support arbitrary numbers of subplans, such as Append.
 * We also store various details to tell the executor when it should be
 * performing partition pruning.
 *
 * Each PartitionedRelPruneInfo describes the partitioning rules for a single
 * partitioned table (a/k/a level of partitioning).  Since a partitioning
 * hierarchy could contain multiple levels, we represent it by a List of
 * PartitionedRelPruneInfos, where the first entry represents the topmost
 * partitioned table and additional entries represent non-leaf child
 * partitions, ordered such that parents appear before their children.
 * Then, since an Append-type node could have multiple partitioning
 * hierarchies among its children, we have an unordered List of those Lists.
 *
 * relids               RelOptInfo.relids of the parent plan node (e.g. Append
 *                      or MergeAppend) to which this PartitionPruneInfo node
 *                      belongs.  The pruning logic ensures that this matches
 *                      the parent plan node's apprelids.
 * prune_infos          List of Lists containing PartitionedRelPruneInfo nodes,
 *                      one sublist per run-time-prunable partition hierarchy
 *                      appearing in the parent plan node's subplans.
 * other_subplans       Indexes of any subplans that are not accounted for
 *                      by any of the PartitionedRelPruneInfo nodes in
 *                      "prune_infos".  These subplans must not be pruned.
 */
typedef struct PartitionPruneInfo
{
    pg_node_attr(no_equal, no_query_jumble)
 
    NodeTag     type;
    Bitmapset  *relids;
    List       *prune_infos;
    Bitmapset  *other_subplans;
} PartitionPruneInfo;
 
/*
 * PartitionedRelPruneInfo - Details required to allow the executor to prune
 * partitions for a single partitioned table.
 *
 * subplan_map[], subpart_map[], and leafpart_rti_map[] are indexed by partition
 * index of the partitioned table referenced by 'rtindex', the partition index
 * being the order that the partitions are defined in the table's
 * PartitionDesc.  For a leaf partition p, subplan_map[p] contains the
 * zero-based index of the partition's subplan in the parent plan's subplan
 * list; it is -1 if the partition is non-leaf or has been pruned.  For a
 * non-leaf partition p, subpart_map[p] contains the zero-based index of that
 * sub-partition's PartitionedRelPruneInfo in the hierarchy's
 * PartitionedRelPruneInfo list; it is -1 if the partition is a leaf or has
 * been pruned.  leafpart_rti_map[p] contains the RT index of a leaf partition
 * if its subplan is in the parent plan' subplan list; it is 0 either if the
 * partition is non-leaf or it is leaf but has been pruned during planning.
 * Note that subplan indexes, as stored in 'subplan_map', are global across the
 * parent plan node, but partition indexes are valid only within a particular
 * hierarchy.  relid_map[p] contains the partition's OID, or 0 if the partition
 * was pruned.
 */
typedef struct PartitionedRelPruneInfo
{
    pg_node_attr(no_equal, no_query_jumble)
 
    NodeTag     type;
 
    /* RT index of partition rel for this level */
    Index       rtindex;
 
    /* Indexes of all partitions which subplans or subparts are present for */
    Bitmapset  *present_parts;
 
    /* Length of the following arrays: */
    int         nparts;
 
    /* subplan index by partition index, or -1 */
    int        *subplan_map pg_node_attr(array_size(nparts));
 
    /* subpart index by partition index, or -1 */
    int        *subpart_map pg_node_attr(array_size(nparts));
 
    /* RT index by partition index, or 0 */
    int        *leafpart_rti_map pg_node_attr(array_size(nparts));
 
    /* relation OID by partition index, or 0 */
    Oid        *relid_map pg_node_attr(array_size(nparts));
 
    /*
     * initial_pruning_steps shows how to prune during executor startup (i.e.,
     * without use of any PARAM_EXEC Params); it is NIL if no startup pruning
     * is required.  exec_pruning_steps shows how to prune with PARAM_EXEC
     * Params; it is NIL if no per-scan pruning is required.
     */
    /* List of PartitionPruneStep */
    List       *initial_pruning_steps;
    /* List of PartitionPruneStep */
    List       *exec_pruning_steps;
 
    /* All PARAM_EXEC Param IDs in exec_pruning_steps */
    Bitmapset  *execparamids;
} PartitionedRelPruneInfo;
 
/*
 * Abstract Node type for partition pruning steps (there are no concrete
 * Nodes of this type).
 *
 * step_id is the global identifier of the step within its pruning context.
 */
typedef struct PartitionPruneStep
{
    pg_node_attr(abstract, no_equal, no_query_jumble)
 
    NodeTag     type;
    int         step_id;
} PartitionPruneStep;
 
/*
 * PartitionPruneStepOp - Information to prune using a set of mutually ANDed
 *                          OpExpr clauses
 *
 * This contains information extracted from up to partnatts OpExpr clauses,
 * where partnatts is the number of partition key columns.  'opstrategy' is the
 * strategy of the operator in the clause matched to the last partition key.
 * 'exprs' contains expressions which comprise the lookup key to be passed to
 * the partition bound search function.  'cmpfns' contains the OIDs of
 * comparison functions used to compare aforementioned expressions with
 * partition bounds.  Both 'exprs' and 'cmpfns' contain the same number of
 * items, up to partnatts items.
 *
 * Once we find the offset of a partition bound using the lookup key, we
 * determine which partitions to include in the result based on the value of
 * 'opstrategy'.  For example, if it were equality, we'd return just the
 * partition that would contain that key or a set of partitions if the key
 * didn't consist of all partitioning columns.  For non-equality strategies,
 * we'd need to include other partitions as appropriate.
 *
 * 'nullkeys' is the set containing the offset of the partition keys (0 to
 * partnatts - 1) that were matched to an IS NULL clause.  This is only
 * considered for hash partitioning as we need to pass which keys are null
 * to the hash partition bound search function.  It is never possible to
 * have an expression be present in 'exprs' for a given partition key and
 * the corresponding bit set in 'nullkeys'.
 */
typedef struct PartitionPruneStepOp
{
    PartitionPruneStep step;
 
    StrategyNumber opstrategy;
    List       *exprs;
    List       *cmpfns;
    Bitmapset  *nullkeys;
} PartitionPruneStepOp;
 
/*
 * PartitionPruneStepCombine - Information to prune using a BoolExpr clause
 *
 * For BoolExpr clauses, we combine the set of partitions determined for each
 * of the argument clauses.
 */
typedef enum PartitionPruneCombineOp
{
    PARTPRUNE_COMBINE_UNION,
    PARTPRUNE_COMBINE_INTERSECT,
} PartitionPruneCombineOp;
 
typedef struct PartitionPruneStepCombine
{
    PartitionPruneStep step;
 
    PartitionPruneCombineOp combineOp;
    List       *source_stepids;
} PartitionPruneStepCombine;
 
 
/*
 * Plan invalidation info
 *
 * We track the objects on which a PlannedStmt depends in two ways:
 * relations are recorded as a simple list of OIDs, and everything else
 * is represented as a list of PlanInvalItems.  A PlanInvalItem is designed
 * to be used with the syscache invalidation mechanism, so it identifies a
 * system catalog entry by cache ID and hash value.
 */
typedef struct PlanInvalItem
{
    pg_node_attr(no_equal, no_query_jumble)
 
    NodeTag     type;
    /* a syscache ID, see utils/syscache.h */
    int         cacheId;
    /* hash value of object's cache lookup key */
    uint32      hashValue;
} PlanInvalItem;
 
/*
 * MonotonicFunction
 *
 * Allows the planner to track monotonic properties of functions.  A function
 * is monotonically increasing if a subsequent call cannot yield a lower value
 * than the previous call.  A monotonically decreasing function cannot yield a
 * higher value on subsequent calls, and a function which is both must return
 * the same value on each call.
 */
typedef enum MonotonicFunction
{
    MONOTONICFUNC_NONE = 0,
    MONOTONICFUNC_INCREASING = (1 << 0),
    MONOTONICFUNC_DECREASING = (1 << 1),
    MONOTONICFUNC_BOTH = MONOTONICFUNC_INCREASING | MONOTONICFUNC_DECREASING,
} MonotonicFunction;
 
/*
 * SubPlanRTInfo
 *
 * Information about which range table entries came from which subquery
 * planning cycles.
 */
typedef struct SubPlanRTInfo
{
    NodeTag     type;
    char       *plan_name;
    Index       rtoffset;
    bool        dummy;
} SubPlanRTInfo;
 
/*
 * ElidedNode
 *
 * Information about nodes elided from the final plan tree: trivial subquery
 * scans, and single-child Append and MergeAppend nodes.
 *
 * plan_node_id is that of the surviving plan node, the sole child of the
 * one which was elided.
 */
typedef struct ElidedNode
{
    NodeTag     type;
    int         plan_node_id;
    NodeTag     elided_type;
    Bitmapset  *relids;
} ElidedNode;
 
#endif                          /* PLANNODES_H */

innerPlan

#define innerPlan

(

node

)

(((Plan *)(node))->righttree)

Definition at line 266 of file plannodes.h.

outerPlan

#define outerPlan

(

node

)

(((Plan *)(node))->lefttree)

Definition at line 267 of file plannodes.h.

RowMarkRequiresRowShareLock

#define RowMarkRequiresRowShareLock

(

marktype

)

((marktype) <= ROW_MARK_KEYSHARE)

Definition at line 1565 of file plannodes.h.

Typedef Documentation

Agg

typedef struct Agg Agg

Append

typedef struct Append Append

BitmapAnd

typedef struct BitmapAnd BitmapAnd

BitmapHeapScan

typedef struct BitmapHeapScan BitmapHeapScan

BitmapIndexScan

typedef struct BitmapIndexScan BitmapIndexScan

BitmapOr

typedef struct BitmapOr BitmapOr

CteScan

typedef struct CteScan CteScan

CustomScan

typedef struct CustomScan CustomScan

ElidedNode

typedef struct ElidedNode ElidedNode

ForeignScan

typedef struct ForeignScan ForeignScan

FunctionScan

typedef struct FunctionScan FunctionScan

Gather

typedef struct Gather Gather

GatherMerge

typedef struct GatherMerge GatherMerge

Group

typedef struct Group Group

Hash

typedef struct Hash Hash

HashJoin

typedef struct HashJoin HashJoin

IncrementalSort

typedef struct IncrementalSort IncrementalSort

IndexOnlyScan

typedef struct IndexOnlyScan IndexOnlyScan

IndexScan

typedef struct IndexScan IndexScan

Join

typedef struct Join Join

Limit

typedef struct Limit Limit

LockRows

typedef struct LockRows LockRows

Material

typedef struct Material Material

Memoize

typedef struct Memoize Memoize

MergeAppend

typedef struct MergeAppend MergeAppend

MergeJoin

typedef struct MergeJoin MergeJoin

ModifyTable

typedef struct ModifyTable ModifyTable

MonotonicFunction

typedef enum MonotonicFunction MonotonicFunction

NamedTuplestoreScan

typedef struct NamedTuplestoreScan NamedTuplestoreScan

NestLoop

typedef struct NestLoop NestLoop

NestLoopParam

typedef struct NestLoopParam NestLoopParam

PartitionedRelPruneInfo

typedef struct PartitionedRelPruneInfo PartitionedRelPruneInfo

PartitionPruneCombineOp

typedef enum PartitionPruneCombineOp PartitionPruneCombineOp

PartitionPruneInfo

typedef struct PartitionPruneInfo PartitionPruneInfo

PartitionPruneStep

typedef struct PartitionPruneStep PartitionPruneStep

PartitionPruneStepCombine

typedef struct PartitionPruneStepCombine PartitionPruneStepCombine

PartitionPruneStepOp

typedef struct PartitionPruneStepOp PartitionPruneStepOp

Plan

typedef struct Plan Plan

PlanInvalItem

typedef struct PlanInvalItem PlanInvalItem

PlannedStmt

typedef struct PlannedStmt PlannedStmt

PlannedStmtOrigin

typedef enum PlannedStmtOrigin PlannedStmtOrigin

PlanRowMark

typedef struct PlanRowMark PlanRowMark

ProjectSet

typedef struct ProjectSet ProjectSet

RecursiveUnion

typedef struct RecursiveUnion RecursiveUnion

Result

typedef struct Result Result

ResultType

typedef enum ResultType ResultType

RowMarkType

typedef enum RowMarkType RowMarkType

SampleScan

typedef struct SampleScan SampleScan

Scan

typedef struct Scan Scan

SeqScan

typedef struct SeqScan SeqScan

SetOp

typedef struct SetOp SetOp

Sort

typedef struct Sort Sort

SubPlanRTInfo

typedef struct SubPlanRTInfo SubPlanRTInfo

SubqueryScan

typedef struct SubqueryScan SubqueryScan

SubqueryScanStatus

typedef enum SubqueryScanStatus SubqueryScanStatus

TableFuncScan

typedef struct TableFuncScan TableFuncScan

TidRangeScan

typedef struct TidRangeScan TidRangeScan

TidScan

typedef struct TidScan TidScan

Unique

typedef struct Unique Unique

ValuesScan

typedef struct ValuesScan ValuesScan

WindowAgg

typedef struct WindowAgg WindowAgg

WorkTableScan

typedef struct WorkTableScan WorkTableScan

Enumeration Type Documentation

MonotonicFunction

enum MonotonicFunction

Enumerator
MONOTONICFUNC_NONE
MONOTONICFUNC_INCREASING
MONOTONICFUNC_DECREASING
MONOTONICFUNC_BOTH

Definition at line 1837 of file plannodes.h.

{
    MONOTONICFUNC_NONE = 0,
    MONOTONICFUNC_INCREASING = (1 << 0),
    MONOTONICFUNC_DECREASING = (1 << 1),
    MONOTONICFUNC_BOTH = MONOTONICFUNC_INCREASING | MONOTONICFUNC_DECREASING,
} MonotonicFunction;

PartitionPruneCombineOp

enum PartitionPruneCombineOp

Enumerator
PARTPRUNE_COMBINE_UNION
PARTPRUNE_COMBINE_INTERSECT

Definition at line 1793 of file plannodes.h.

{
    PARTPRUNE_COMBINE_UNION,
    PARTPRUNE_COMBINE_INTERSECT,
} PartitionPruneCombineOp;

PlannedStmtOrigin

enum PlannedStmtOrigin

Enumerator
PLAN_STMT_UNKNOWN
PLAN_STMT_INTERNAL
PLAN_STMT_STANDARD
PLAN_STMT_CACHE_GENERIC
PLAN_STMT_CACHE_CUSTOM

Definition at line 35 of file plannodes.h.

{
    PLAN_STMT_UNKNOWN = 0,      /* plan origin is not yet known */
    PLAN_STMT_INTERNAL,         /* generated internally by a query */
    PLAN_STMT_STANDARD,         /* standard planned statement */
    PLAN_STMT_CACHE_GENERIC,    /* Generic cached plan */
    PLAN_STMT_CACHE_CUSTOM,     /* Custom cached plan */
} PlannedStmtOrigin;

ResultType

enum ResultType

Enumerator
RESULT_TYPE_GATING
RESULT_TYPE_SCAN
RESULT_TYPE_JOIN
RESULT_TYPE_UPPER
RESULT_TYPE_MINMAX

Definition at line 275 of file plannodes.h.

{
    RESULT_TYPE_GATING,         /* project or one-time-filter outer plan */
    RESULT_TYPE_SCAN,           /* replace empty scan */
    RESULT_TYPE_JOIN,           /* replace empty join */
    RESULT_TYPE_UPPER,          /* replace degenerate upper rel */
    RESULT_TYPE_MINMAX          /* implement minmax aggregate */
} ResultType;

RowMarkType

enum RowMarkType

Enumerator
ROW_MARK_EXCLUSIVE
ROW_MARK_NOKEYEXCLUSIVE
ROW_MARK_SHARE
ROW_MARK_KEYSHARE
ROW_MARK_REFERENCE
ROW_MARK_COPY

Definition at line 1555 of file plannodes.h.

{
    ROW_MARK_EXCLUSIVE,         /* obtain exclusive tuple lock */
    ROW_MARK_NOKEYEXCLUSIVE,    /* obtain no-key exclusive tuple lock */
    ROW_MARK_SHARE,             /* obtain shared tuple lock */
    ROW_MARK_KEYSHARE,          /* obtain keyshare tuple lock */
    ROW_MARK_REFERENCE,         /* just fetch the TID, don't lock it */
    ROW_MARK_COPY,              /* physically copy the row value */
} RowMarkType;

SubqueryScanStatus

enum SubqueryScanStatus

Enumerator
SUBQUERY_SCAN_UNKNOWN
SUBQUERY_SCAN_TRIVIAL
SUBQUERY_SCAN_NONTRIVIAL

Definition at line 766 of file plannodes.h.

{
    SUBQUERY_SCAN_UNKNOWN,
    SUBQUERY_SCAN_TRIVIAL,
    SUBQUERY_SCAN_NONTRIVIAL,
} SubqueryScanStatus;