/*------------------------------------------------------------------------- * * primnodes.h * Definitions for parse tree/query tree ("primitive") nodes. * * * Copyright (c) 1994, Regents of the University of California * * $Id: primnodes.h,v 1.33 1999/08/16 02:17:39 tgl Exp $ * *------------------------------------------------------------------------- */ #ifndef PRIMNODES_H #define PRIMNODES_H #include "access/attnum.h" #include "nodes/pg_list.h" #include "utils/fcache.h" /* ---------------------------------------------------------------- * node definitions * ---------------------------------------------------------------- */ /* ---------------- * Resdom (Result Domain) * resno - attribute number * restype - type of the resdom * restypmod - type-specific modifier of the result * resname - name of the resdom (could be NULL) * reskey - order of key in a sort (for those > 0) * reskeyop - sort operator Oid * resgroupref - set to nonzero if referenced from a group by clause * resjunk - set to true to eliminate the attribute * from final target list * * ---------------- */ typedef struct Resdom { NodeTag type; AttrNumber resno; Oid restype; int32 restypmod; char *resname; Index reskey; Oid reskeyop; Index resgroupref; bool resjunk; } Resdom; /* ------------- * Fjoin * initialized - true if the Fjoin has already been initialized for * the current target list evaluation * nNodes - The number of Iter nodes returning sets that the * node will flatten * outerList - 1 or more Iter nodes * inner - exactly one Iter node. We eval every node in the * outerList once then eval the inner node to completion * pair the outerList result vector with each inner * result to form the full result. When the inner has * been exhausted, we get the next outer result vector * and reset the inner. * results - The complete (flattened) result vector * alwaysNull - a null vector to indicate sets with a cardinality of * 0, we treat them as the set {NULL}. */ typedef struct Fjoin { NodeTag type; bool fj_initialized; int fj_nNodes; List *fj_innerNode; DatumPtr fj_results; BoolPtr fj_alwaysDone; } Fjoin; /* ---------------- * Expr * typeOid - oid of the type of this expression * opType - type of this expression * oper - the Oper node if it is an OPER_EXPR or the * Func node if it is a FUNC_EXPR * args - arguments to this expression * ---------------- */ typedef enum OpType { OP_EXPR, FUNC_EXPR, OR_EXPR, AND_EXPR, NOT_EXPR, SUBPLAN_EXPR } OpType; typedef struct Expr { NodeTag type; Oid typeOid; /* oid of the type of this expr */ OpType opType; /* type of the op */ Node *oper; /* could be Oper or Func or SubPlan */ List *args; /* list of argument nodes */ } Expr; /* ---------------- * Var * varno - index of this var's relation in the range table * (could be INNER or OUTER) * varattno - attribute number of this var, or zero for all * vartype - pg_type tuple oid for the type of this var * vartypmod - pg_attribute typmod value * varlevelsup - for subquery variables referencing outer relations * varnoold - keep varno around in case it got changed to INNER/ * OUTER (see match_varid) * varoattno - attribute number of this var * [ '(varnoold varoattno) was varid -ay 2/95] * ---------------- */ #define INNER 65000 #define OUTER 65001 #define PRS2_CURRENT_VARNO 1 #define PRS2_NEW_VARNO 2 typedef struct Var { NodeTag type; Index varno; AttrNumber varattno; Oid vartype; int32 vartypmod; Index varlevelsup; /* erased by upper optimizer */ Index varnoold; /* only used by optimizer */ AttrNumber varoattno; /* only used by optimizer */ } Var; /* ---------------- * Oper * opno - PG_OPERATOR OID of the operator * opid - PG_PROC OID for the operator * opresulttype - PG_TYPE OID of the operator's return value * opsize - size of return result (cached by executor) * op_fcache - XXX comment me. * * ---- * NOTE: in the good old days 'opno' used to be both (or either, or * neither) the pg_operator oid, and/or the pg_proc oid depending * on the postgres module in question (parser->pg_operator, * executor->pg_proc, planner->both), the mood of the programmer, * and the phase of the moon (rumors that it was also depending on the day * of the week are probably false). To make things even more postgres-like * (i.e. a mess) some comments were referring to 'opno' using the name * 'opid'. Anyway, now we have two separate fields, and of course that * immediately removes all bugs from the code... [ sp :-) ]. * ---------------- */ typedef struct Oper { NodeTag type; Oid opno; Oid opid; Oid opresulttype; int opsize; FunctionCachePtr op_fcache; } Oper; /* ---------------- * Const * consttype - PG_TYPE OID of the constant's value * constlen - length in bytes of the constant's value * constvalue - the constant's value * constisnull - whether the constant is null * (if true, the other fields are undefined) * constbyval - whether the information in constvalue * if 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. * constisset - whether the const represents a set. The const * value corresponding will be the query that defines * the set. * ---------------- */ typedef struct Const { NodeTag type; Oid consttype; int constlen; Datum constvalue; bool constisnull; bool constbyval; bool constisset; bool constiscast; } Const; /* ---------------- * Param * paramkind - specifies the kind of parameter. The possible values * for this field are specified in "params.h", and they are: * * PARAM_NAMED: The parameter has a name, i.e. something * like `$.salary' or `$.foobar'. * In this case field `paramname' must be a valid Name. * * PARAM_NUM: The parameter has only a numeric identifier, * i.e. something like `$1', `$2' etc. * The number is contained in the `paramid' field. * * PARAM_NEW: Used in PRS2 rule, similar to PARAM_NAMED. * The `paramname' and `paramid' refer to the "NEW" tuple * The `pramname' is the attribute name and `paramid' * is the attribute number. * * PARAM_OLD: Same as PARAM_NEW, but in this case we refer to * the "OLD" tuple. * * paramid - numeric identifier for literal-constant parameters ("$1") * paramname - attribute name for tuple-substitution parameters ("$.foo") * paramtype - PG_TYPE OID of the parameter's value * param_tlist - allows for projection in a param node. * ---------------- */ typedef struct Param { NodeTag type; int paramkind; AttrNumber paramid; char *paramname; Oid paramtype; List *param_tlist; } Param; /* ---------------- * Func * funcid - PG_FUNCTION OID of the function * functype - PG_TYPE OID of the function's return value * funcisindex - the function can be evaluated by scanning an index * (set during query optimization) * funcsize - size of return result (cached by executor) * func_fcache - runtime state while running this function. Where * we are in the execution of the function if it * returns more than one value, etc. * See utils/fcache.h * func_tlist - projection of functions returning tuples * func_planlist - result of planning this func, if it's a PQ func * ---------------- */ typedef struct Func { NodeTag type; Oid funcid; Oid functype; bool funcisindex; int funcsize; FunctionCachePtr func_fcache; List *func_tlist; List *func_planlist; } Func; /* ---------------- * Iter * can anyone explain what this is for? Seems to have something to do * with evaluation of functions that return sets... * ---------------- */ typedef struct Iter { NodeTag type; Node *iterexpr; Oid itertype; /* type of the iter expr (use for type * checking) */ } Iter; /* ---------------- * Aggref * aggname - name of the aggregate * basetype - base type Oid of the aggregate * aggtype - type Oid of final result of the aggregate * target - attribute or expression we are aggregating on * aggno - index to ecxt_values * ---------------- */ typedef struct Aggref { NodeTag type; char *aggname; Oid basetype; Oid aggtype; Node *target; int aggno; bool usenulls; } Aggref; /* ---------------- * SubLink * subLinkType - EXISTS, ALL, ANY, EXPR * useor - TRUE for <> * lefthand - list of Var/Const nodes on the left * oper - list of Oper nodes * subselect - subselect as Query* or parsetree * ---------------- */ typedef enum SubLinkType { EXISTS_SUBLINK, ALL_SUBLINK, ANY_SUBLINK, EXPR_SUBLINK } SubLinkType; typedef struct SubLink { NodeTag type; SubLinkType subLinkType; bool useor; List *lefthand; List *oper; Node *subselect; } SubLink; /* ---------------- * Array * arrayelemtype - type of the array's elements (homogenous!) * arrayelemlength - length of that type * arrayelembyval - is the element type pass-by-value? * arrayndim - number of dimensions of the array * arraylow - base for array indexing * arrayhigh - limit for array indexing * arraylen - total length of array object * ---------------- * * memo from mao: the array support we inherited from 3.1 is just * wrong. when time exists, we should redesign this stuff to get * around a bunch of unfortunate implementation decisions made there. */ typedef struct Array { NodeTag type; Oid arrayelemtype; int arrayelemlength; bool arrayelembyval; int arrayndim; IntArray arraylow; IntArray arrayhigh; int arraylen; } Array; /* ---------------- * 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. * * refattrlength - total length of array object * refelemtype - type of the result of the subscript operation * refelemlength - length of the array element type * refelembyval - is the element type pass-by-value? * refupperindexpr - expressions that evaluate to upper array indexes * reflowerindexpr - expressions that evaluate to lower array indexes * refexpr - the expression that evaluates to an array value * refassgnexpr - expression for the source value, or NULL if fetch * * 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: array types can be fixed-length (refattrlength > 0), but only * when the element type is itself fixed-length. Otherwise they are * varlena structures and have refattrlength = -1. In any case, * an array type is never pass-by-value. * * Note: currently, refelemtype is NOT the element type, but the array type, * when doing subarray fetch or either type of store. It would be cleaner * to add more fields so we can distinguish the array element type from the * result type of the subscript operator... * ---------------- */ typedef struct ArrayRef { NodeTag type; int refattrlength; int refelemlength; Oid refelemtype; bool refelembyval; List *refupperindexpr; List *reflowerindexpr; Node *refexpr; Node *refassgnexpr; } ArrayRef; #endif /* PRIMNODES_H */