/* ------------------------------------------------------------------------- * * primnodes.h * Definitions for "primitive" node types, those that are used in more * than one of the parse/plan/execute stages of the query pipeline. * Currently, these are mostly nodes for executable expressions * and join trees. * * * Portions Copyright (c) 1996-2012, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * Portions Copyright (c) 2010-2012 Postgres-XC Development Group * Portions Copyright (c) 2021, openGauss Contributors * * src/include/nodes/primnodes.h * * ------------------------------------------------------------------------- */ #ifndef PRIMNODES_H #define PRIMNODES_H #include "access/attnum.h" #include "nodes/pg_list.h" #include "nodes/params.h" #include "db4ai/db4ai.h" /* ---------------------------------------------------------------- * node definitions * ---------------------------------------------------------------- */ /* * Alias - * specifies an alias for a range variable; the alias might also * specify renaming of columns within the table. * * Note: colnames is a list of Value nodes (always strings). In Alias structs * associated with RTEs, there may be entries corresponding to dropped * columns; these are normally empty strings (""). See parsenodes.h for info. */ typedef struct Alias { NodeTag type; char* aliasname; /* aliased rel name (never qualified) */ List* colnames; /* optional list of column aliases */ } Alias; typedef enum InhOption { INH_NO, /* Do NOT scan child tables */ INH_YES, /* DO scan child tables */ INH_DEFAULT /* Use current SQL_inheritance option */ } InhOption; /* What to do at commit time for temporary relations */ typedef enum OnCommitAction { ONCOMMIT_NOOP, /* No ON COMMIT clause (do nothing) */ ONCOMMIT_PRESERVE_ROWS, /* ON COMMIT PRESERVE ROWS (do nothing) */ ONCOMMIT_DELETE_ROWS, /* ON COMMIT DELETE ROWS */ ONCOMMIT_DROP /* ON COMMIT DROP */ } OnCommitAction; // If enable_compress is off, the table will not be compressed no matter // which option is specified. // typedef enum OptCompress { COMPRESS_NO = 0, COMPRESS_LOW, COMPRESS_MIDDLE, COMPRESS_HIGH, } OptCompress; /* How to handle rows that duplicate unique key values */ typedef enum OnDuplicateAction { DUPLICATE_ERROR = 0, DUPLICATE_IGNORE, DUPLICATE_REPLACE } OnDuplicate; /* * RangeVar - range variable, used in FROM clauses * * Also used to represent table names in utility statements; there, the alias * field is not used, and inhOpt shows whether to apply the operation * recursively to child tables. In some contexts it is also useful to carry * a TEMP table indication here. */ typedef struct RangeVar { NodeTag type; char* catalogname; /* the catalog (database) name, or NULL */ char* schemaname; /* the schema name, or NULL */ char* relname; /* the relation/sequence name */ char* partitionname; /* partition name, if is a partition */ char* subpartitionname; /* partition name, if is a subpartition */ InhOption inhOpt; /* expand rel by inheritance? recursively act * on children? */ char relpersistence; /* see RELPERSISTENCE_* in pg_class.h */ Alias* alias; /* table alias & optional column aliases */ int location; /* token location, or -1 if unknown */ bool ispartition; /* for partition action */ bool issubpartition; /* for subpartition action */ List* partitionKeyValuesList; bool isbucket; /* is the RangeVar means a hash bucket id ? */ List* buckets; /* the corresponding bucketid list */ int length; #ifdef ENABLE_MOT Oid foreignOid; #endif bool withVerExpr; List* partitionNameList; /* for FROM table PARTITION (p1, subp2, ...) clause */ List* indexhints; /* a list of b mode index hint indexHintDefinition members */ } RangeVar; /* * IntoClause - target information for SELECT INTO, CREATE TABLE AS, and * CREATE MATERIALIZED VIEW */ typedef struct IntoClause { NodeTag type; RangeVar* rel; /* target relation name */ List* colNames; /* column names to assign, or NIL */ List* options; /* options from WITH clause */ OnCommitAction onCommit; /* what do we do at COMMIT? */ int8 row_compress; /* row compression flag */ char* tableSpaceName; /* table space to use, or NULL */ bool skipData; /* true for WITH NO DATA */ bool ivm; /* true for WITH IVM */ char relkind; /* RELKIND_RELATION or RELKIND_MATVIEW */ List* userVarList; /* user define variables list */ List* copyOption; /* copyOption for select...into statement */ char* filename; /* filename for select...into statement */ bool is_outfile; /* true for outfile */ #ifdef PGXC struct DistributeBy* distributeby; /* distribution to use, or NULL */ struct PGXCSubCluster* subcluster; /* subcluster node members */ #endif List* tableElts; /* column definitions(list of ColumnDef) */ Node *autoIncStart; /* DefElem for AUTO_INCREMENT = value*/ OnDuplicateAction onduplicate; /* how to handle rows that duplicate unique key values */ } IntoClause; /* ---------------------------------------------------------------- * node types for executable expressions * ---------------------------------------------------------------- */ /* * Expr - generic superclass for executable-expression nodes * * All node types that are used in executable expression trees should derive * from Expr (that is, have Expr as their first field). Since Expr only * contains NodeTag, this is a formality, but it is an easy form of * documentation. See also the ExprState node types in execnodes.h. */ typedef struct Expr { NodeTag type; double selec; } Expr; /* * Var - expression node representing a variable (ie, a table column) * * Note: during parsing/planning, varnoold/varoattno are always just copies * of varno/varattno. At the tail end of planning, Var nodes appearing in * upper-level plan nodes are reassigned to point to the outputs of their * subplans; for example, in a join node varno becomes INNER_VAR or OUTER_VAR * and varattno becomes the index of the proper element of that subplan's * target list. But varnoold/varoattno continue to hold the original values. * The code doesn't really need varnoold/varoattno, but they are very useful * for debugging and interpreting completed plans, so we keep them around. */ #define INNER_VAR 65000 /* reference to inner subplan */ #define OUTER_VAR 65001 /* reference to outer subplan */ #define INDEX_VAR 65002 /* reference to index column */ #define MERGEJOIN_VAR 65003 /* reference to merge join results */ #define IS_SPECIAL_VARNO(varno) ((varno) >= INNER_VAR) /* Symbols for the indexes of the special RTE entries in rules */ #define PRS2_OLD_VARNO 1 #define PRS2_NEW_VARNO 2 typedef struct Var { Expr xpr; Index varno; /* index of this var's relation in the range * table, or INNER_VAR/OUTER_VAR/INDEX_VAR */ AttrNumber varattno; /* attribute number of this var, or zero for * all */ Oid vartype; /* pg_type OID for the type of this var */ int32 vartypmod; /* pg_attribute typmod value */ Oid varcollid; /* OID of collation, or InvalidOid if none */ Index varlevelsup; /* for subquery variables referencing outer * relations; 0 in a normal var, >0 means N * levels up */ Index varnoold; /* original value of varno, for debugging */ AttrNumber varoattno; /* original value of varattno */ int location; /* token location, or -1 if unknown */ } Var; /* * Const */ typedef struct Const { Expr xpr; Oid consttype; /* pg_type OID of the constant's datatype */ int32 consttypmod; /* typmod value, if any */ Oid constcollid; /* OID of collation, or InvalidOid if none */ int constlen; /* typlen of the constant's datatype */ Datum constvalue; /* the constant's value */ bool constisnull; /* whether the constant is null (if true, * constvalue is undefined) */ bool constbyval; /* whether this datatype is passed by value. * If true, then all the information is stored * in the Datum. If false, then the Datum * contains a pointer to the information. */ int location; /* token location, or -1 if unknown */ bool ismaxvalue; /*is the Const represent maxValue, maxValue is used for partition */ Cursor_Data cursor_data; } Const; /* ---------------- * Param * paramkind - specifies the kind of parameter. The possible values * for this field are: * * PARAM_EXTERN: The parameter value is supplied from outside the plan. * Such parameters are numbered from 1 to n. * * PARAM_EXEC: The parameter is an internal executor parameter, used * for passing values into and out of sub-queries or from * nestloop joins to their inner scans. * For historical reasons, such parameters are numbered from 0. * These numbers are independent of PARAM_EXTERN numbers. * * PARAM_SUBLINK: The parameter represents an output column of a SubLink * node's sub-select. The column number is contained in the * `paramid' field. (This type of Param is converted to * PARAM_EXEC during planning.) * * Note: currently, paramtypmod is valid for PARAM_SUBLINK Params, and for * PARAM_EXEC Params generated from them; it is always -1 for PARAM_EXTERN * params, since the APIs that supply values for such parameters don't carry * any typmod info. * ---------------- */ typedef enum ParamKind { PARAM_EXTERN, PARAM_EXEC, PARAM_SUBLINK } ParamKind; typedef struct Param { Expr xpr; ParamKind paramkind; /* kind of parameter. See above */ int paramid; /* numeric ID for parameter */ Oid paramtype; /* pg_type OID of parameter's datatype */ int32 paramtypmod; /* typmod value, if known */ Oid paramcollid; /* OID of collation, or InvalidOid if none */ int location; /* token location, or -1 if unknown */ Oid tableOfIndexType; /* type Oid of table of (wait to discard) */ Oid recordVarTypOid; /* package record var's composite type oid */ List* tableOfIndexTypeList; /* type Oid list of table of, max size 6 */ bool is_bind_param; char* name; bool is_pkg_var; List* args; } Param; /* * Aggref * * The aggregate's args list is a targetlist, ie, a list of TargetEntry nodes * (before Postgres 9.0 it was just bare expressions). The non-resjunk TLEs * represent the aggregate's regular arguments (if any) and resjunk TLEs can * be added at the end to represent ORDER BY expressions that are not also * arguments. As in a top-level Query, the TLEs can be marked with * ressortgroupref indexes to let them be referenced by SortGroupClause * entries in the aggorder and/or aggdistinct lists. This represents ORDER BY * and DISTINCT operations to be applied to the aggregate input rows before * they are passed to the transition function. The grammar only allows a * simple "DISTINCT" specifier for the arguments, but we use the full * query-level representation to allow more code sharing. */ typedef struct Aggref { Expr xpr; Oid aggfnoid; /* pg_proc Oid of the aggregate */ Oid aggtype; /* type Oid of result of the aggregate */ Oid aggcollid; /* OID of collation of result */ Oid inputcollid; /* OID of collation that function should use */ #ifdef PGXC Oid aggtrantype; /* type Oid of transition results */ bool agghas_collectfn; /* is collection function available */ int8 aggstage; /* in which stage this aggref is in */ #endif /* PGXC */ #ifdef USE_SPQ AggSplit aggsplittype; /* expected agg-splitting mode of parent Agg */ #endif List* aggdirectargs; /* direct arguments, if an ordered-set agg */ List* args; /* arguments and sort expressions */ List* aggorder; /* ORDER BY (list of SortGroupClause) */ List* aggdistinct; /* DISTINCT (list of SortGroupClause) */ bool aggiskeep; bool aggkpfirst; bool aggstar; /* TRUE if argument list was really '*' */ bool aggvariadic; /* true if variadic arguments have been * combined into an array last argument */ char aggkind; /* aggregate kind (see pg_aggregate.h) */ Index agglevelsup; /* > 0 if agg belongs to outer query */ int location; /* token location, or -1 if unknown */ List* aggargtypes; /* type Oids of direct and aggregated args */ int aggsplit; /* expected agg-splitting mode of parent Agg */ Oid aggtranstype; /* type Oid of aggregate's transition value */ Expr *aggfilter; /* FILTER expression, if any */ } Aggref; /* * GroupingFunc * * A GroupingFunc is a GROUPING(...) expression, which behaves in many ways * like an aggregate function (e.g. it "belongs" to a specific query level, * which might not be the one immediately containing it), but also differs in * an important respect: it never evaluates its arguments, they merely * designate expressions from the GROUP BY clause of the query level to which * it belongs. * * The spec defines the evaluation of GROUPING() purely by syntactic * replacement, but we make it a real expression for optimization purposes so * that one Agg node can handle multiple grouping sets at once. Evaluating the * result only needs the column positions to check against the grouping set * being projected. However, for EXPLAIN to produce meaningful output, we have * to keep the original expressions around, since expression deparse does not * give us any feasible way to get at the GROUP BY clause. * * Also, we treat two GroupingFunc nodes as equal if they have equal arguments * lists and agglevelsup, without comparing the refs and cols annotations. * * In raw parse output we have only the args list; parse analysis fills in the * refs list, and the planner fills in the cols list. */ typedef struct GroupingFunc { Expr xpr; List* args; /* arguments, not evaluated but kept for * benefit of EXPLAIN etc. */ List* refs; /* ressortgrouprefs of arguments */ List* cols; /* actual column positions set by planner */ Index agglevelsup; /* same as Aggref.agglevelsup */ int location; /* token location */ } GroupingFunc; typedef struct GroupingId { Expr xpr; } GroupingId; /* * WindowFunc */ typedef struct WindowFunc { Expr xpr; Oid winfnoid; /* pg_proc Oid of the function */ Oid wintype; /* type Oid of result of the window function */ Oid wincollid; /* OID of collation of result */ Oid inputcollid; /* OID of collation that function should use */ List* args; /* arguments to the window function */ Index winref; /* index of associated WindowClause */ bool winstar; /* TRUE if argument list was really '*' */ bool winagg; /* is function a simple aggregate? */ int location; /* token location, or -1 if unknown */ List* keep_args; List* winkporder; bool winkpfirst; #ifdef USE_SPQ bool windistinct; /* TRUE if it's agg(DISTINCT ...) */ #endif bool is_from_last; /* used for window function nth_value */ bool is_ignore_nulls; /* used for window function nth_value */ } WindowFunc; /* * pseudo-column "ROWNUM" */ typedef struct Rownum { Expr xpr; Oid rownumcollid; /* OID of collation of result */ int location; /* token location, or -1 if unknown */ } Rownum; typedef struct PriorExpr { Expr xpr; Node *node; } PriorExpr; /* ---------------- * ArrayRef: describes an array subscripting operation * * An ArrayRef can describe fetching a single element from an array, * fetching a subarray (array slice), storing a single element into * an array, or storing a slice. The "store" cases work with an * initial array value and a source value that is inserted into the * appropriate part of the array; the result of the operation is an * entire new modified array value. * * If reflowerindexpr = NIL, then we are fetching or storing a single array * element at the subscripts given by refupperindexpr. Otherwise we are * fetching or storing an array slice, that is a rectangular subarray * with lower and upper bounds given by the index expressions. * reflowerindexpr must be the same length as refupperindexpr when it * is not NIL. * * Note: the result datatype is the element type when fetching a single * element; but it is the array type when doing subarray fetch or either * type of store. * ---------------- */ typedef struct ArrayRef { Expr xpr; Oid refarraytype; /* type of the array proper */ Oid refelemtype; /* type of the array elements */ int32 reftypmod; /* typmod of the array (and elements too) */ Oid refcollid; /* OID of collation, or InvalidOid if none */ List* refupperindexpr; /* expressions that evaluate to upper array * indexes */ List* reflowerindexpr; /* expressions that evaluate to lower array * indexes */ Expr* refexpr; /* the expression that evaluates to an array * value */ Expr* refassgnexpr; /* expression for the source value, or NULL if * fetch */ } ArrayRef; /* * CoercionContext - distinguishes the allowed set of type casts * * NB: ordering of the alternatives is significant; later (larger) values * allow more casts than earlier ones. */ typedef enum CoercionContext { COERCION_IMPLICIT, /* coercion in context of expression */ COERCION_ASSIGNMENT, /* coercion in context of assignment */ COERCION_EXPLICIT, /* explicit cast operation */ COERCION_UNKNOWN = 0xFFFFFFFE /* unknown */ } CoercionContext; /* * CoercionForm - information showing how to display a function-call node * * NB: equal() ignores CoercionForm fields, therefore this *must* not carry * any semantically significant information. We need that behavior so that * the planner will consider equivalent implicit and explicit casts to be * equivalent. In cases where those actually behave differently, the coercion * function's arguments will be different. */ typedef enum CoercionForm { COERCE_EXPLICIT_CALL, /* display as a function call */ COERCE_EXPLICIT_CAST, /* display as an explicit cast */ COERCE_IMPLICIT_CAST, /* implicit cast, so hide it */ COERCE_DONTCARE /* special case for planner */ } CoercionForm; /* * FuncExpr - expression node for a function call */ typedef struct FuncExpr { Expr xpr; Oid funcid; /* PG_PROC OID of the function */ Oid funcresulttype; /* PG_TYPE OID of result value */ int32 funcresulttype_orig; /* PG_TYPE OID of original result value */ bool funcretset; /* true if function returns set */ /* true if variadic arguments have been combined into an array last argument */ bool funcvariadic; CoercionForm funcformat; /* how to display this function call */ Oid funccollid; /* OID of collation of result */ Oid inputcollid; /* OID of collation that function should use */ char* fmtstr; /* fmt string */ char* nlsfmtstr; /* nls fmt string */ List* args; /* arguments to the function */ int location; /* token location, or -1 if unknown */ Oid refSynOid; /* PG_SYNONYM OID of the referenced synonym */ } FuncExpr; /* * NamedArgExpr - a named argument of a function * * This node type can only appear in the args list of a FuncCall or FuncExpr * node. We support pure positional call notation (no named arguments), * named notation (all arguments are named), and mixed notation (unnamed * arguments followed by named ones). * * Parse analysis sets argnumber to the positional index of the argument, * but doesn't rearrange the argument list. * * The planner will convert argument lists to pure positional notation * during expression preprocessing, so execution never sees a NamedArgExpr. */ typedef struct NamedArgExpr { Expr xpr; Expr* arg; /* the argument expression */ char* name; /* the name */ int argnumber; /* argument's number in positional notation */ int location; /* argument name location, or -1 if unknown */ } NamedArgExpr; /* * OpExpr - expression node for an operator invocation * * Semantically, this is essentially the same as a function call. * * Note that opfuncid is not necessarily filled in immediately on creation * of the node. The planner makes sure it is valid before passing the node * tree to the executor, but during parsing/planning opfuncid can be 0. */ typedef struct OpExpr { Expr xpr; Oid opno; /* PG_OPERATOR OID of the operator */ Oid opfuncid; /* PG_PROC OID of underlying function */ Oid opresulttype; /* PG_TYPE OID of result value */ bool opretset; /* true if operator returns set */ Oid opcollid; /* OID of collation of result */ Oid inputcollid; /* OID of collation that operator should use */ List* args; /* arguments to the operator (1 or 2) */ int location; /* token location, or -1 if unknown */ } OpExpr; /* * DistinctExpr - expression node for "x IS DISTINCT FROM y" * * Except for the nodetag, this is represented identically to an OpExpr * referencing the "=" operator for x and y. * We use "=", not the more obvious "<>", because more datatypes have "=" * than "<>". This means the executor must invert the operator result. * Note that the operator function won't be called at all if either input * is NULL, since then the result can be determined directly. */ typedef OpExpr DistinctExpr; /* * NullIfExpr - a NULLIF expression * * Like DistinctExpr, this is represented the same as an OpExpr referencing * the "=" operator for x and y. */ typedef OpExpr NullIfExpr; /* * ScalarArrayOpExpr - expression node for "scalar op ANY/ALL (array)" * * The operator must yield boolean. It is applied to the left operand * and each element of the righthand array, and the results are combined * with OR or AND (for ANY or ALL respectively). The node representation * is almost the same as for the underlying operator, but we need a useOr * flag to remember whether it's ANY or ALL, and we don't have to store * the result type (or the collation) because it must be boolean. * * A ScalarArrayOpExpr with a valid hashfuncid is evaluated during execution * by building a hash table containing the Const values from the rhs arg. * This table is probed during expression evaluation. Only useOr=true * ScalarArrayOpExpr with Const arrays on the rhs can have the hashfuncid * field set. See convert_saop_to_hashed_saop(). * by building a hash table containing the Const values from the RHS arg. * This table is probed during expression evaluation. The planner will set * hashfuncid to the hash function which must be used to build and probe the * hash table. The executor determines if it should use hash-based checks or * the more traditional means based on if the hashfuncid is set or not. * * When performing hashed NOT IN, the negfuncid will also be set to the * equality function which the hash table must use to build and probe the hash * table. opno and opfuncid will remain set to the <> operator and its * corresponding function and won't be used during execution. For * non-hashtable based NOT INs, negfuncid will be set to InvalidOid. See * convert_saop_to_hashed_saop(). */ typedef struct ScalarArrayOpExpr { Expr xpr; Oid opno; /* PG_OPERATOR OID of the operator */ Oid opfuncid; /* PG_PROC OID of underlying function */ Oid hashfuncid; /* PG_PROC OID of hash func or InvalidOid */ Oid negfuncid; /* PG_PROC OID of negator of opfuncid function or InvalidOid. See above */ bool useOr; /* true for ANY, false for ALL */ Oid inputcollid; /* OID of collation that operator should use */ List* args; /* the scalar and array operands */ int location; /* token location, or -1 if unknown */ } ScalarArrayOpExpr; /* * BoolExpr - expression node for the basic Boolean operators AND, OR, NOT * * Notice the arguments are given as a List. For NOT, of course the list * must always have exactly one element. For AND and OR, the executor can * handle any number of arguments. The parser generally treats AND and OR * as binary and so it typically only produces two-element lists, but the * optimizer will flatten trees of AND and OR nodes to produce longer lists * when possible. There are also a few special cases where more arguments * can appear before optimization. */ typedef enum BoolExprType { AND_EXPR, OR_EXPR, NOT_EXPR } BoolExprType; typedef struct BoolExpr { Expr xpr; BoolExprType boolop; List* args; /* arguments to this expression */ int location; /* token location, or -1 if unknown */ } BoolExpr; /* * SubLink * * A SubLink represents a subselect appearing in an expression, and in some * cases also the combining operator(s) just above it. The subLinkType * indicates the form of the expression represented: * EXISTS_SUBLINK EXISTS(SELECT ...) * ALL_SUBLINK (lefthand) op ALL (SELECT ...) * ANY_SUBLINK (lefthand) op ANY (SELECT ...) * ROWCOMPARE_SUBLINK (lefthand) op (SELECT ...) * EXPR_SUBLINK (SELECT with single targetlist item ...) * ARRAY_SUBLINK ARRAY(SELECT with single targetlist item ...) * CTE_SUBLINK WITH query (never actually part of an expression) * For ALL, ANY, and ROWCOMPARE, the lefthand is a list of expressions of the * same length as the subselect's targetlist. ROWCOMPARE will *always* have * a list with more than one entry; if the subselect has just one target * then the parser will create an EXPR_SUBLINK instead (and any operator * above the subselect will be represented separately). Note that both * ROWCOMPARE and EXPR require the subselect to deliver only one row. * ALL, ANY, and ROWCOMPARE require the combining operators to deliver boolean * results. ALL and ANY combine the per-row results using AND and OR * semantics respectively. * ARRAY requires just one target column, and creates an array of the target * column's type using any number of rows resulting from the subselect. * * SubLink is classed as an Expr node, but it is not actually executable; * it must be replaced in the expression tree by a SubPlan node during * planning. * * NOTE: in the raw output of gram.y, testexpr contains just the raw form * of the lefthand expression (if any), and operName is the String name of * the combining operator. Also, subselect is a raw parsetree. During parse * analysis, the parser transforms testexpr into a complete boolean expression * that compares the lefthand value(s) to PARAM_SUBLINK nodes representing the * output columns of the subselect. And subselect is transformed to a Query. * This is the representation seen in saved rules and in the rewriter. * * In EXISTS, EXPR, and ARRAY SubLinks, testexpr and operName are unused and * are always null. * * The CTE_SUBLINK case never occurs in actual SubLink nodes, but it is used * in SubPlans generated for WITH subqueries. */ typedef enum SubLinkType { EXISTS_SUBLINK, ALL_SUBLINK, ANY_SUBLINK, ROWCOMPARE_SUBLINK, EXPR_SUBLINK, ARRAY_SUBLINK, #ifdef USE_SPQ NOT_EXISTS_SUBLINK, /* spq uses NOT_EXIST_SUBLINK to implement correlated left anti semijoin. */ #endif CTE_SUBLINK /* for SubPlans only */ } SubLinkType; typedef struct SubLink { Expr xpr; SubLinkType subLinkType; /* see above */ Node* testexpr; /* outer-query test for ALL/ANY/ROWCOMPARE */ List* operName; /* originally specified operator name */ Node* subselect; /* subselect as Query* or parsetree */ int location; /* token location, or -1 if unknown */ } SubLink; /* * SubPlan - executable expression node for a subplan (sub-SELECT) * * The planner replaces SubLink nodes in expression trees with SubPlan * nodes after it has finished planning the subquery. SubPlan references * a sub-plantree stored in the subplans list of the toplevel PlannedStmt. * (We avoid a direct link to make it easier to copy expression trees * without causing multiple processing of the subplan.) * * In an ordinary subplan, testexpr points to an executable expression * (OpExpr, an AND/OR tree of OpExprs, or RowCompareExpr) for the combining * operator(s); the left-hand arguments are the original lefthand expressions, * and the right-hand arguments are PARAM_EXEC Param nodes representing the * outputs of the sub-select. (NOTE: runtime coercion functions may be * inserted as well.) This is just the same expression tree as testexpr in * the original SubLink node, but the PARAM_SUBLINK nodes are replaced by * suitably numbered PARAM_EXEC nodes. * * If the sub-select becomes an initplan rather than a subplan, the executable * expression is part of the outer plan's expression tree (and the SubPlan * node itself is not, but rather is found in the outer plan's initPlan * list). In this case testexpr is NULL to avoid duplication. * * The planner also derives lists of the values that need to be passed into * and out of the subplan. Input values are represented as a list "args" of * expressions to be evaluated in the outer-query context (currently these * args are always just Vars, but in principle they could be any expression). * The values are assigned to the global PARAM_EXEC params indexed by parParam * (the parParam and args lists must have the same ordering). setParam is a * list of the PARAM_EXEC params that are computed by the sub-select, if it * is an initplan; they are listed in order by sub-select output column * position. (parParam and setParam are integer Lists, not Bitmapsets, * because their ordering is significant.) * * Also, the planner computes startup and per-call costs for use of the * SubPlan. Note that these include the cost of the subquery proper, * evaluation of the testexpr if any, and any hashtable management overhead. */ typedef struct SubPlan { Expr xpr; /* Fields copied from original SubLink: */ SubLinkType subLinkType; /* see above */ /* The combining operators, transformed to an executable expression: */ Node* testexpr; /* OpExpr or RowCompareExpr expression tree */ List* paramIds; /* IDs of Params embedded in the above */ /* Identification of the Plan tree to use: */ int plan_id; /* Index (from 1) in PlannedStmt.subplans */ /* Identification of the SubPlan for EXPLAIN and debugging purposes: */ char* plan_name; /* A name assigned during planning */ /* Extra data useful for determining subplan's output type: */ Oid firstColType; /* Type of first column of subplan result */ int32 firstColTypmod; /* Typmod of first column of subplan result */ Oid firstColCollation; /* Collation of first column of subplan result */ /* Information about execution strategy: */ /* TRUE to store subselect output in a hash table (implies we are doing "IN") */ bool useHashTable; /* TRUE if it's okay to return FALSE when the spec result is UNKNOWN; this allows much simpler handling of null values */ bool unknownEqFalse; /* Information for passing params into and out of the subselect: */ /* setParam and parParam are lists of integers (param IDs) */ List* setParam; /* initplan subqueries have to set these Params for parent plan */ List* parParam; /* indices of input Params from parent plan */ List* args; /* exprs to pass as parParam values */ /* Estimated execution costs: */ Cost startup_cost; /* one-time setup cost */ Cost per_call_cost; /* cost for each subplan evaluation */ #ifdef USE_SPQ bool is_initplan; /* SPQ: Is the subplan implemented as an initplan? */ bool is_multirow; /* SPQ: May the subplan return more than one row? */ #endif } SubPlan; /* * AlternativeSubPlan - expression node for a choice among SubPlans * * The subplans are given as a List so that the node definition need not * change if there's ever more than two alternatives. For the moment, * though, there are always exactly two; and the first one is the fast-start * plan. */ typedef struct AlternativeSubPlan { Expr xpr; List* subplans; /* SubPlan(s) with equivalent results */ } AlternativeSubPlan; /* ---------------- * FieldSelect * * FieldSelect represents the operation of extracting one field from a tuple * value. At runtime, the input expression is expected to yield a rowtype * Datum. The specified field number is extracted and returned as a Datum. * ---------------- */ typedef struct FieldSelect { Expr xpr; Expr* arg; /* input expression */ AttrNumber fieldnum; /* attribute number of field to extract */ Oid resulttype; /* type of the field (result type of this * node) */ int32 resulttypmod; /* output typmod (usually -1) */ Oid resultcollid; /* OID of collation of the field */ } FieldSelect; /* ---------------- * FieldStore * * FieldStore represents the operation of modifying one field in a tuple * value, yielding a new tuple value (the input is not touched!). Like * the assign case of ArrayRef, this is used to implement UPDATE of a * portion of a column. * * A single FieldStore can actually represent updates of several different * fields. The parser only generates FieldStores with single-element lists, * but the planner will collapse multiple updates of the same base column * into one FieldStore. * ---------------- */ typedef struct FieldStore { Expr xpr; Expr* arg; /* input tuple value */ List* newvals; /* new value(s) for field(s) */ List* fieldnums; /* integer list of field attnums */ Oid resulttype; /* type of result (same as type of arg) */ /* Like RowExpr, we deliberately omit a typmod and collation here */ } FieldStore; /* ---------------- * RelabelType * * RelabelType represents a "dummy" type coercion between two binary- * compatible datatypes, such as reinterpreting the result of an OID * expression as an int4. It is a no-op at runtime; we only need it * to provide a place to store the correct type to be attributed to * the expression result during type resolution. (We can't get away * with just overwriting the type field of the input expression node, * so we need a separate node to show the coercion's result type.) * ---------------- */ typedef struct RelabelType { Expr xpr; Expr* arg; /* input expression */ Oid resulttype; /* output type of coercion expression */ int32 resulttypmod; /* output typmod (usually -1) */ Oid resultcollid; /* OID of collation, or InvalidOid if none */ CoercionForm relabelformat; /* how to display this node */ int location; /* token location, or -1 if unknown */ } RelabelType; /* ---------------- * CoerceViaIO * * CoerceViaIO represents a type coercion between two types whose textual * representations are compatible, implemented by invoking the source type's * typoutput function then the destination type's typinput function. * ---------------- */ typedef struct CoerceViaIO { Expr xpr; Expr* arg; /* input expression */ char* fmtstr; char* nlsfmtstr; Oid resulttype; /* output type of coercion */ /* output typmod is not stored, but is presumed -1 */ Oid resultcollid; /* OID of collation, or InvalidOid if none */ CoercionForm coerceformat; /* how to display this node */ int location; /* token location, or -1 if unknown */ } CoerceViaIO; /* ---------------- * ArrayCoerceExpr * * ArrayCoerceExpr represents a type coercion from one array type to another, * which is implemented by applying the indicated element-type coercion * function to each element of the source array. If elemfuncid is InvalidOid * then the element types are binary-compatible, but the coercion still * requires some effort (we have to fix the element type ID stored in the * array header). * ---------------- */ typedef struct ArrayCoerceExpr { Expr xpr; Expr* arg; /* input expression (yields an array) */ char* fmtstr; /* fmr string */ char* nlsfmtstr; /* nls fmt string */ Oid elemfuncid; /* OID of element coercion function, or 0 */ Oid resulttype; /* output type of coercion (an array type) */ int32 resulttypmod; /* output typmod (also element typmod) */ Oid resultcollid; /* OID of collation, or InvalidOid if none */ bool isExplicit; /* conversion semantics flag to pass to func */ CoercionForm coerceformat; /* how to display this node */ int location; /* token location, or -1 if unknown */ } ArrayCoerceExpr; /* ---------------- * ConvertRowtypeExpr * * ConvertRowtypeExpr represents a type coercion from one composite type * to another, where the source type is guaranteed to contain all the columns * needed for the destination type plus possibly others; the columns need not * be in the same positions, but are matched up by name. This is primarily * used to convert a whole-row value of an inheritance child table into a * valid whole-row value of its parent table's rowtype. * ---------------- */ typedef struct ConvertRowtypeExpr { Expr xpr; Expr* arg; /* input expression */ Oid resulttype; /* output type (always a composite type) */ /* Like RowExpr, we deliberately omit a typmod and collation here */ CoercionForm convertformat; /* how to display this node */ int location; /* token location, or -1 if unknown */ } ConvertRowtypeExpr; /* ---------- * CollateExpr - COLLATE * * The planner replaces CollateExpr with RelabelType during expression * preprocessing, so execution never sees a CollateExpr. * ---------- */ typedef struct CollateExpr { Expr xpr; Expr* arg; /* input expression */ Oid collOid; /* collation's OID */ int location; /* token location, or -1 if unknown */ } CollateExpr; /* ---------- * CaseExpr - a CASE expression * * We support two distinct forms of CASE expression: * CASE WHEN boolexpr THEN expr [ WHEN boolexpr THEN expr ... ] * CASE testexpr WHEN compexpr THEN expr [ WHEN compexpr THEN expr ... ] * These are distinguishable by the "arg" field being NULL in the first case * and the testexpr in the second case. * * In the raw grammar output for the second form, the condition expressions * of the WHEN clauses are just the comparison values. Parse analysis * converts these to valid boolean expressions of the form * CaseTestExpr '=' compexpr * where the CaseTestExpr node is a placeholder that emits the correct * value at runtime. This structure is used so that the testexpr need be * evaluated only once. Note that after parse analysis, the condition * expressions always yield boolean. * * Note: we can test whether a CaseExpr has been through parse analysis * yet by checking whether casetype is InvalidOid or not. * ---------- */ typedef struct CaseExpr { Expr xpr; Oid casetype; /* type of expression result */ Oid casecollid; /* OID of collation, or InvalidOid if none */ Expr* arg; /* implicit equality comparison argument */ List* args; /* the arguments (list of WHEN clauses) */ Expr* defresult; /* the default result (ELSE clause) */ int location; /* token location, or -1 if unknown */ bool fromDecode; /* whether is parsed from decode expr, no need to (de-)serialize */ } CaseExpr; /* * CaseWhen - one arm of a CASE expression */ typedef struct CaseWhen { Expr xpr; Expr* expr; /* condition expression */ Expr* result; /* substitution result */ int location; /* token location, or -1 if unknown */ } CaseWhen; /* * Placeholder node for the test value to be processed by a CASE expression. * This is effectively like a Param, but can be implemented more simply * since we need only one replacement value at a time. * * We also use this in nested UPDATE expressions. * See transformAssignmentIndirection(). */ typedef struct CaseTestExpr { Expr xpr; Oid typeId; /* type for substituted value */ int32 typeMod; /* typemod for substituted value */ Oid collation; /* collation for the substituted value */ } CaseTestExpr; /* * ArrayExpr - an ARRAY[] expression * * Note: if multidims is false, the constituent expressions all yield the * scalar type identified by element_typeid. If multidims is true, the * constituent expressions all yield arrays of element_typeid (ie, the same * type as array_typeid); at runtime we must check for compatible subscripts. */ typedef struct ArrayExpr { Expr xpr; Oid array_typeid; /* type of expression result */ Oid array_collid; /* OID of collation, or InvalidOid if none */ Oid element_typeid; /* common type of array elements */ List* elements; /* the array elements or sub-arrays */ bool multidims; /* true if elements are sub-arrays */ int location; /* token location, or -1 if unknown */ } ArrayExpr; /* * RowExpr - a ROW() expression * * Note: the list of fields must have a one-for-one correspondence with * physical fields of the associated rowtype, although it is okay for it * to be shorter than the rowtype. That is, the N'th list element must * match up with the N'th physical field. When the N'th physical field * is a dropped column (attisdropped) then the N'th list element can just * be a NULL constant. (This case can only occur for named composite types, * not RECORD types, since those are built from the RowExpr itself rather * than vice versa.) It is important not to assume that length(args) is * the same as the number of columns logically present in the rowtype. * * colnames provides field names in cases where the names can't easily be * obtained otherwise. Names *must* be provided if row_typeid is RECORDOID. * If row_typeid identifies a known composite type, colnames can be NIL to * indicate the type's cataloged field names apply. Note that colnames can * be non-NIL even for a composite type, and typically is when the RowExpr * was created by expanding a whole-row Var. This is so that we can retain * the column alias names of the RTE that the Var referenced (which would * otherwise be very difficult to extract from the parsetree). Like the * args list, colnames is one-for-one with physical fields of the rowtype. */ typedef struct RowExpr { Expr xpr; List* args; /* the fields */ Oid row_typeid; /* RECORDOID or a composite type's ID */ /* * Note: we deliberately do NOT store a typmod. Although a typmod will be * associated with specific RECORD types at runtime, it will differ for * different backends, and so cannot safely be stored in stored * parsetrees. We must assume typmod -1 for a RowExpr node. * * We don't need to store a collation either. The result type is * necessarily composite, and composite types never have a collation. */ CoercionForm row_format; /* how to display this node */ List* colnames; /* list of String, or NIL */ int location; /* token location, or -1 if unknown */ } RowExpr; /* * RowCompareExpr - row-wise comparison, such as (a, b) <= (1, 2) * * We support row comparison for any operator that can be determined to * act like =, <>, <, <=, >, or >= (we determine this by looking for the * operator in btree opfamilies). Note that the same operator name might * map to a different operator for each pair of row elements, since the * element datatypes can vary. * * A RowCompareExpr node is only generated for the < <= > >= cases; * the = and <> cases are translated to simple AND or OR combinations * of the pairwise comparisons. However, we include = and <> in the * RowCompareType enum for the convenience of parser logic. */ typedef enum RowCompareType { /* Values of this enum are chosen to match btree strategy numbers */ ROWCOMPARE_LT = 1, /* BTLessStrategyNumber */ ROWCOMPARE_LE = 2, /* BTLessEqualStrategyNumber */ ROWCOMPARE_EQ = 3, /* BTEqualStrategyNumber */ ROWCOMPARE_GE = 4, /* BTGreaterEqualStrategyNumber */ ROWCOMPARE_GT = 5, /* BTGreaterStrategyNumber */ ROWCOMPARE_NE = 6 /* no such btree strategy */ } RowCompareType; typedef struct RowCompareExpr { Expr xpr; RowCompareType rctype; /* LT LE GE or GT, never EQ or NE */ List* opnos; /* OID list of pairwise comparison ops */ List* opfamilies; /* OID list of containing operator families */ List* inputcollids; /* OID list of collations for comparisons */ List* largs; /* the left-hand input arguments */ List* rargs; /* the right-hand input arguments */ } RowCompareExpr; /* * CoalesceExpr - a COALESCE expression */ typedef struct CoalesceExpr { Expr xpr; Oid coalescetype; /* type of expression result */ Oid coalescecollid; /* OID of collation, or InvalidOid if none */ List* args; /* the arguments */ int location; /* token location, or -1 if unknown */ bool isnvl; /* is CoalesceExpr NVL ? */ } CoalesceExpr; /* * MinMaxExpr - a GREATEST or LEAST function */ typedef enum MinMaxOp { IS_GREATEST, IS_LEAST } MinMaxOp; typedef struct MinMaxExpr { Expr xpr; Oid minmaxtype; /* common type of arguments and result */ Oid minmaxcollid; /* OID of collation of result */ Oid inputcollid; /* OID of collation that function should use */ MinMaxOp op; /* function to execute */ List* args; /* the arguments */ int location; /* token location, or -1 if unknown */ Oid cmptype; /* the comparison type */ List* cmpargs; /* the comparison arguments */ } MinMaxExpr; /* * XmlExpr - various SQL/XML functions requiring special grammar productions * * 'name' carries the "NAME foo" argument (already XML-escaped). * 'named_args' and 'arg_names' represent an xml_attribute list. * 'args' carries all other arguments. * * Note: result type/typmod/collation are not stored, but can be deduced * from the XmlExprOp. The type/typmod fields are just used for display * purposes, and are NOT necessarily the true result type of the node. * (We also use type == InvalidOid to mark a not-yet-parse-analyzed XmlExpr.) */ typedef enum XmlExprOp { IS_XMLCONCAT, /* XMLCONCAT(args) */ IS_XMLELEMENT, /* XMLELEMENT(name, xml_attributes, args) */ IS_XMLFOREST, /* XMLFOREST(xml_attributes) */ IS_XMLPARSE, /* XMLPARSE(text, is_doc, preserve_ws) */ IS_XMLPI, /* XMLPI(name [, args]) */ IS_XMLROOT, /* XMLROOT(xml, version, standalone) */ IS_XMLSERIALIZE, /* XMLSERIALIZE(is_document, xmlval) */ IS_DOCUMENT /* xmlval IS DOCUMENT */ } XmlExprOp; typedef enum { XMLOPTION_DOCUMENT, XMLOPTION_CONTENT } XmlOptionType; typedef struct XmlExpr { Expr xpr; XmlExprOp op; /* xml function ID */ char* name; /* name in xml(NAME foo ...) syntaxes */ List* named_args; /* non-XML expressions for xml_attributes */ List* arg_names; /* parallel list of Value strings */ List* args; /* list of expressions */ XmlOptionType xmloption; /* DOCUMENT or CONTENT */ Oid type; /* target type/typmod for XMLSERIALIZE */ int32 typmod; int location; /* token location, or -1 if unknown */ } XmlExpr; typedef struct PrefixKey { Expr xpr; Expr* arg; /* should be a ColumnRef or Var */ int length; /* prefix length */ } PrefixKey; /* ---------------- * NullTest * * NullTest represents the operation of testing a value for NULLness. * The appropriate test is performed and returned as a boolean Datum. * * When argisrow is false, this simply represents a test for the null value. * * When argisrow is true, the input expression must yield a rowtype, and * the node implements "row IS [NOT] NULL" per the SQL standard. This * includes checking individual fields for NULLness when the row datum * itself isn't NULL. * * NOTE: the combination of a rowtype input and argisrow==false does NOT * correspond to the SQL notation "row IS [NOT] NULL"; instead, this case * represents the SQL notation "row IS [NOT] DISTINCT FROM NULL". * ---------------- */ typedef enum NullTestType { IS_NULL, IS_NOT_NULL } NullTestType; typedef struct NullTest { Expr xpr; Expr* arg; /* input expression */ NullTestType nulltesttype; /* IS NULL, IS NOT NULL */ bool argisrow; /* T to perform field-by-field null checks */ } NullTest; /* ---------------- * NanTest * * NanTest represents the operation of testing a value for Nan. * The appropriate test is performed and returned as a boolean Datum. * ---------------- */ typedef enum NanTestType { IS_NAN, IS_NOT_NAN } NanTestType; typedef struct NanTest { Expr xpr; Expr* arg; /* input expression */ NanTestType nantesttype; /* IS NAN, IS NOT NAN */ } NanTest; /* ---------------- * InfiniteTest * * InfiniteTest represents the operation of testing a value for Infinite. * The appropriate test is performed and returned as a boolean Datum. * ---------------- */ typedef enum InfiniteTestType { IS_INFINITE, IS_NOT_INFINITE } InfiniteTestType; typedef struct InfiniteTest { Expr xpr; Expr* arg; /* input expression */ InfiniteTestType infinitetesttype; /* IS INFINITE, IS NOT INFINITE */ } InfiniteTest; /* * BooleanTest * * BooleanTest represents the operation of determining whether a boolean * is TRUE, FALSE, or UNKNOWN (ie, NULL). All six meaningful combinations * are supported. Note that a NULL input does *not* cause a NULL result. * The appropriate test is performed and returned as a boolean Datum. */ typedef enum BoolTestType { IS_TRUE, IS_NOT_TRUE, IS_FALSE, IS_NOT_FALSE, IS_UNKNOWN, IS_NOT_UNKNOWN } BoolTestType; typedef struct BooleanTest { Expr xpr; Expr* arg; /* input expression */ BoolTestType booltesttype; /* test type */ } BooleanTest; /* HashFilter indicate that filter tuple using hash */ typedef struct HashFilter { Expr xpr; List* arg; /* input expression */ List* typeOids; /* type oid list of var for filter */ List* nodeList; /* Node indices where data is located */ // uint2 *bucketMap; } HashFilter; /* * EstSPNode * * For some expression, we can't estimate them though vars under them. Therefore, * we should keep them and get the vars under them to get an overall estimation. */ typedef struct EstSPNode { Expr xpr; Node* expr; List* varlist; } EstSPNode; /* * CoerceToDomain * * CoerceToDomain represents the operation of coercing a value to a domain * type. At runtime (and not before) the precise set of constraints to be * checked will be determined. If the value passes, it is returned as the * result; if not, an error is raised. Note that this is equivalent to * RelabelType in the scenario where no constraints are applied. */ typedef struct CoerceToDomain { Expr xpr; Expr* arg; /* input expression */ Oid resulttype; /* domain type ID (result type) */ int32 resulttypmod; /* output typmod (currently always -1) */ Oid resultcollid; /* OID of collation, or InvalidOid if none */ CoercionForm coercionformat; /* how to display this node */ int location; /* token location, or -1 if unknown */ } CoerceToDomain; /* * Placeholder node for the value to be processed by a domain's check * constraint. This is effectively like a Param, but can be implemented more * simply since we need only one replacement value at a time. * * Note: the typeId/typeMod/collation will be set from the domain's base type, * not the domain itself. This is because we shouldn't consider the value * to be a member of the domain if we haven't yet checked its constraints. */ typedef struct CoerceToDomainValue { Expr xpr; Oid typeId; /* type for substituted value */ int32 typeMod; /* typemod for substituted value */ Oid collation; /* collation for the substituted value */ int location; /* token location, or -1 if unknown */ } CoerceToDomainValue; /* * Placeholder node for a DEFAULT marker in an INSERT or UPDATE command. * * This is not an executable expression: it must be replaced by the actual * column default expression during rewriting. But it is convenient to * treat it as an expression node during parsing and rewriting. */ typedef struct SetToDefault { Expr xpr; Oid typeId; /* type for substituted value */ int32 typeMod; /* typemod for substituted value */ Oid collation; /* collation for the substituted value */ int location; /* token location, or -1 if unknown */ bool lrchild_unknown; } SetToDefault; /* value expressions (changed for client_logic feature) */ typedef struct ExprWithComma { NodeTag type; Expr *xpr; int comma_before_loc; } ExprWithComma; /* * Node representing [WHERE] CURRENT OF cursor_name * * CURRENT OF is a bit like a Var, in that it carries the rangetable index * of the target relation being constrained; this aids placing the expression * correctly during planning. We can assume however that its "levelsup" is * always zero, due to the syntactic constraints on where it can appear. * * The referenced cursor can be represented either as a hardwired string * or as a reference to a run-time parameter of type REFCURSOR. The latter * case is for the convenience of plpgsql. */ typedef struct CurrentOfExpr { Expr xpr; Index cvarno; /* RT index of target relation */ char* cursor_name; /* name of referenced cursor, or NULL */ int cursor_param; /* refcursor parameter number, or 0 */ } CurrentOfExpr; /* SetVariableExpr used for getting guc variable's value */ typedef struct { Expr xpr; char* name; Expr* value; bool is_session; /* true is session, only used in B compability */ bool is_global; /* true is global, only used in B compability */ } SetVariableExpr; /* -------------------- * TargetEntry - * a target entry (used in query target lists) * * Strictly speaking, a TargetEntry isn't an expression node (since it can't * be evaluated by ExecEvalExpr). But we treat it as one anyway, since in * very many places it's convenient to process a whole query targetlist as a * single expression tree. * * In a SELECT's targetlist, resno should always be equal to the item's * ordinal position (counting from 1). However, in an INSERT or UPDATE * targetlist, resno represents the attribute number of the destination * column for the item; so there may be missing or out-of-order resnos. * It is even legal to have duplicated resnos; consider * UPDATE table SET arraycol[1] = ..., arraycol[2] = ..., ... * The two meanings come together in the executor, because the planner * transforms INSERT/UPDATE tlists into a normalized form with exactly * one entry for each column of the destination table. Before that's * happened, however, it is risky to assume that resno == position. * Generally get_tle_by_resno() should be used rather than list_nth() * to fetch tlist entries by resno, and only in SELECT should you assume * that resno is a unique identifier. * * resname is required to represent the correct column name in non-resjunk * entries of top-level SELECT targetlists, since it will be used as the * column title sent to the frontend. In most other contexts it is only * a debugging aid, and may be wrong or even NULL. (In particular, it may * be wrong in a tlist from a stored rule, if the referenced column has been * renamed by ALTER TABLE since the rule was made. Also, the planner tends * to store NULL rather than look up a valid name for tlist entries in * non-toplevel plan nodes.) In resjunk entries, resname should be either * a specific system-generated name (such as "ctid") or NULL; anything else * risks confusing ExecGetJunkAttribute! * * ressortgroupref is used in the representation of ORDER BY, GROUP BY, and * DISTINCT items. Targetlist entries with ressortgroupref=0 are not * sort/group items. If ressortgroupref>0, then this item is an ORDER BY, * GROUP BY, and/or DISTINCT target value. No two entries in a targetlist * may have the same nonzero ressortgroupref --- but there is no particular * meaning to the nonzero values, except as tags. (For example, one must * not assume that lower ressortgroupref means a more significant sort key.) * The order of the associated SortGroupClause lists determine the semantics. * * resorigtbl/resorigcol identify the source of the column, if it is a * simple reference to a column of a base table (or view). If it is not * a simple reference, these fields are zeroes. * * If resjunk is true then the column is a working column (such as a sort key) * that should be removed from the final output of the query. Resjunk columns * must have resnos that cannot duplicate any regular column's resno. Also * note that there are places that assume resjunk columns come after non-junk * columns. * -------------------- */ typedef struct TargetEntry { Expr xpr; Expr* expr; /* expression to evaluate */ AttrNumber resno; /* attribute number (see notes above) */ char* resname; /* name of the column (could be NULL) */ Index ressortgroupref; /* nonzero if referenced by a sort/group * clause */ Oid resorigtbl; /* OID of column's source table */ AttrNumber resorigcol; /* column's number in source table */ bool resjunk; /* set to true to eliminate the attribute from * final target list */ Index rtindex; /* used when multiple modifying. It indicates the resultRelation * to which this TLE belongs. */ bool isStartWithPseudo; } TargetEntry; /* mainly support Start with */ typedef struct PseudoTargetEntry { NodeTag type; TargetEntry *tle; TargetEntry *srctle; } PseudoTargetEntry; /* ---------------------------------------------------------------- * node types for join trees * * The leaves of a join tree structure are RangeTblRef nodes. Above * these, JoinExpr nodes can appear to denote a specific kind of join * or qualified join. Also, FromExpr nodes can appear to denote an * ordinary cross-product join ("FROM foo, bar, baz WHERE ..."). * FromExpr is like a JoinExpr of jointype JOIN_INNER, except that it * may have any number of child nodes, not just two. * * NOTE: the top level of a Query's jointree is always a FromExpr. * Even if the jointree contains no rels, there will be a FromExpr. * * NOTE: the qualification expressions present in JoinExpr nodes are * *in addition to* the query's main WHERE clause, which appears as the * qual of the top-level FromExpr. The reason for associating quals with * specific nodes in the jointree is that the position of a qual is critical * when outer joins are present. (If we enforce a qual too soon or too late, * that may cause the outer join to produce the wrong set of NULL-extended * rows.) If all joins are inner joins then all the qual positions are * semantically interchangeable. * * NOTE: in the raw output of gram.y, a join tree contains RangeVar, * RangeSubselect, and RangeFunction nodes, which are all replaced by * RangeTblRef nodes during the parse analysis phase. Also, the top-level * FromExpr is added during parse analysis; the grammar regards FROM and * WHERE as separate. * ---------------------------------------------------------------- */ /* * RangeTblRef - reference to an entry in the query's rangetable * * We could use direct pointers to the RT entries and skip having these * nodes, but multiple pointers to the same node in a querytree cause * lots of headaches, so it seems better to store an index into the RT. */ typedef struct RangeTblRef { NodeTag type; int rtindex; } RangeTblRef; /* ---------- * JoinExpr - for SQL JOIN expressions * * isNatural, usingClause, and quals are interdependent. The user can write * only one of NATURAL, USING(), or ON() (this is enforced by the grammar). * If he writes NATURAL then parse analysis generates the equivalent USING() * list, and from that fills in "quals" with the right equality comparisons. * If he writes USING() then "quals" is filled with equality comparisons. * If he writes ON() then only "quals" is set. Note that NATURAL/USING * are not equivalent to ON() since they also affect the output column list. * * alias is an Alias node representing the AS alias-clause attached to the * join expression, or NULL if no clause. NB: presence or absence of the * alias has a critical impact on semantics, because a join with an alias * restricts visibility of the tables/columns inside it. * * During parse analysis, an RTE is created for the Join, and its index * is filled into rtindex. This RTE is present mainly so that Vars can * be created that refer to the outputs of the join. The planner sometimes * generates JoinExprs internally; these can have rtindex = 0 if there are * no join alias variables referencing such joins. * ---------- */ typedef struct JoinExpr { NodeTag type; JoinType jointype; /* type of join */ bool isNatural; /* Natural join? Will need to shape table */ bool isAsof; /* Asof join? */ Node* larg; /* left subtree */ Node* rarg; /* right subtree */ List* usingClause; /* USING clause, if any (list of String) */ Node* quals; /* qualifiers on join, if any */ Alias* alias; /* user-written alias clause, if any */ int rtindex; /* RT index assigned for join, or 0 */ bool is_straight_join; /* set true if straight_join */ bool is_apply_join; /* set true when on cross apply or outer apply join */ } JoinExpr; /* ---------- * FromExpr - represents a FROM ... WHERE ... construct * * This is both more flexible than a JoinExpr (it can have any number of * children, including zero) and less so --- we don't need to deal with * aliases and so on. The output column set is implicitly just the union * of the outputs of the children. * ---------- */ typedef struct FromExpr { NodeTag type; List* fromlist; /* List of join subtrees */ Node* quals; /* qualifiers on join, if any */ } FromExpr; #ifdef PGXC /* ---------- * DistributionType - how to distribute the data * * ---------- */ typedef enum DistributionType { DISTTYPE_REPLICATION, /* Replicated */ DISTTYPE_HASH, /* Hash partitioned */ DISTTYPE_ROUNDROBIN, /* Round Robin */ DISTTYPE_MODULO, /* Modulo partitioned */ DISTTYPE_HIDETAG, /* Use a hidden column as distribute column */ DISTTYPE_LIST, /* List */ DISTTYPE_RANGE /* Range */ } DistributionType; typedef struct ListSliceDefState { NodeTag type; char* name; List* boundaries; /* list of boundary(multi-values) */ char* datanode_name; } ListSliceDefState; typedef struct DistState { NodeTag type; /* * 'r' range slice * 'l' list slice */ char strategy; /* list of slice definition, like: * ListSliceDefState or RangePartitionDefState or RangePartitionStartEndDefState */ List* sliceList; char* refTableName; } DistState; /* ---------- * DistributeBy - represents a DISTRIBUTE BY clause in a CREATE TABLE statement * * ---------- */ typedef struct DistributeBy { NodeTag type; DistributionType disttype; /* Distribution type */ List* colname; /* Distribution column name */ DistState* distState; /* Slice Definitions */ Oid referenceoid; /* table oid that slice references, InvalidOid if none */ } DistributeBy; /* ---------- * SubClusterType - type of subcluster used * * ---------- */ typedef enum PGXCSubClusterType { SUBCLUSTER_NONE, SUBCLUSTER_NODE, SUBCLUSTER_GROUP } PGXCSubClusterType; /* ---------- * PGXCSubCluster - Subcluster on which a table can be created * * ---------- */ typedef struct PGXCSubCluster { NodeTag type; PGXCSubClusterType clustertype; /* Subcluster type */ List* members; /* List of nodes or groups */ } PGXCSubCluster; #endif typedef struct { NodeTag type; Oid relid; AttrNumber attno; char* relname; char* attname; bool indexcol; List* indexoids; bool indexpath; } IndexVar; typedef struct UpsertExpr { NodeTag type; UpsertAction upsertAction; /* DO NOTHING or UPDATE? */ /* DUPLICATE KEY UPDATE */ List* updateTlist; /* List of UPDATE TargetEntrys */ List* exclRelTlist; /* tlist of the 'EXCLUDED' pseudo relation */ int exclRelIndex; /* RT index of 'EXCLUDED' relation */ Node* upsertWhere; /* Qualifiers for upsert's update clause to check */ } UpsertExpr; #ifdef USE_SPQ /* * DMLActionExpr * * Represents the expression which introduces the action in a SplitUpdate statement */ typedef struct DMLActionExpr { Expr xpr; } DMLActionExpr; #endif /* * DB4AI */ #define DB4AI_SNAPSHOT_VERSION_DELIMITER 1 #define DB4AI_SNAPSHOT_VERSION_SEPARATOR 2 #endif /* PRIMNODES_H */