diff options
Diffstat (limited to 'src/backend/parser/parse_oper.c')
| -rw-r--r-- | src/backend/parser/parse_oper.c | 214 |
1 files changed, 117 insertions, 97 deletions
diff --git a/src/backend/parser/parse_oper.c b/src/backend/parser/parse_oper.c index 7d3919a1fc6..a44a740dc92 100644 --- a/src/backend/parser/parse_oper.c +++ b/src/backend/parser/parse_oper.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/parser/parse_oper.c,v 1.43 2000/11/11 19:49:26 thomas Exp $ + * $Header: /cvsroot/pgsql/src/backend/parser/parse_oper.c,v 1.44 2000/11/16 22:30:28 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -38,25 +38,21 @@ static void op_error(char *op, Oid arg1, Oid arg2); static void unary_op_error(char *op, Oid arg, bool is_left_op); +/* Select an ordering operator for the given datatype */ Oid any_ordering_op(Oid restype) { - Operator order_op; Oid order_opid; - order_op = oper("<", restype, restype, TRUE); - if (!HeapTupleIsValid(order_op)) - { + order_opid = oper_oid("<", restype, restype, true); + if (!OidIsValid(order_opid)) elog(ERROR, "Unable to identify an ordering operator '%s' for type '%s'" "\n\tUse an explicit ordering operator or modify the query", "<", typeidTypeName(restype)); - } - order_opid = oprid(order_op); - return order_opid; } -/* given operator, return the operator OID */ +/* given operator tuple, return the operator OID */ Oid oprid(Operator op) { @@ -502,9 +498,10 @@ oper_select_candidate(int nargs, /* oper_exact() - * Given operator, and arguments, return oper struct or NULL. - * Inputs: - * arg1, arg2: Type IDs + * Given operator, types of arg1 and arg2, return oper struct or NULL. + * + * NOTE: on success, the returned object is a syscache entry. The caller + * must ReleaseSysCache() the entry when done with it. */ static Operator oper_exact(char *op, Oid arg1, Oid arg2) @@ -517,20 +514,21 @@ oper_exact(char *op, Oid arg1, Oid arg2) else if ((arg2 == UNKNOWNOID) && (arg1 != InvalidOid)) arg2 = arg1; - tup = SearchSysCacheTuple(OPERNAME, - PointerGetDatum(op), - ObjectIdGetDatum(arg1), - ObjectIdGetDatum(arg2), - CharGetDatum('b')); + tup = SearchSysCache(OPERNAME, + PointerGetDatum(op), + ObjectIdGetDatum(arg1), + ObjectIdGetDatum(arg2), + CharGetDatum('b')); return (Operator) tup; -} /* oper_exact() */ +} /* oper_inexact() - * Given operator, types of arg1, and arg2, return oper struct or NULL. - * Inputs: - * arg1, arg2: Type IDs + * Given operator, types of arg1 and arg2, return oper struct or NULL. + * + * NOTE: on success, the returned object is a syscache entry. The caller + * must ReleaseSysCache() the entry when done with it. */ static Operator oper_inexact(char *op, Oid arg1, Oid arg2) @@ -556,11 +554,11 @@ oper_inexact(char *op, Oid arg1, Oid arg2) /* Or found exactly one? Then proceed... */ else if (ncandidates == 1) { - tup = SearchSysCacheTuple(OPERNAME, - PointerGetDatum(op), - ObjectIdGetDatum(candidates->args[0]), - ObjectIdGetDatum(candidates->args[1]), - CharGetDatum('b')); + tup = SearchSysCache(OPERNAME, + PointerGetDatum(op), + ObjectIdGetDatum(candidates->args[0]), + ObjectIdGetDatum(candidates->args[1]), + CharGetDatum('b')); Assert(HeapTupleIsValid(tup)); } @@ -572,43 +570,68 @@ oper_inexact(char *op, Oid arg1, Oid arg2) targetOids = oper_select_candidate(2, inputOids, candidates); if (targetOids != NULL) { - tup = SearchSysCacheTuple(OPERNAME, - PointerGetDatum(op), - ObjectIdGetDatum(targetOids[0]), - ObjectIdGetDatum(targetOids[1]), - CharGetDatum('b')); + tup = SearchSysCache(OPERNAME, + PointerGetDatum(op), + ObjectIdGetDatum(targetOids[0]), + ObjectIdGetDatum(targetOids[1]), + CharGetDatum('b')); } else tup = NULL; } return (Operator) tup; -} /* oper_inexact() */ +} -/* oper() - * Given operator, types of arg1, and arg2, return oper struct. - * Inputs: - * arg1, arg2: Type IDs +/* oper() -- search for a binary operator + * Given operator name, types of arg1 and arg2, return oper struct. + * + * If no matching operator found, return NULL if noError is true, + * raise an error if it is false. + * + * NOTE: on success, the returned object is a syscache entry. The caller + * must ReleaseSysCache() the entry when done with it. */ Operator -oper(char *opname, Oid ltypeId, Oid rtypeId, bool noWarnings) +oper(char *opname, Oid ltypeId, Oid rtypeId, bool noError) { HeapTuple tup; /* check for exact match on this operator... */ if (HeapTupleIsValid(tup = oper_exact(opname, ltypeId, rtypeId))) - { - } + return (Operator) tup; + /* try to find a match on likely candidates... */ - else if (HeapTupleIsValid(tup = oper_inexact(opname, ltypeId, rtypeId))) - { - } - else if (!noWarnings) + if (HeapTupleIsValid(tup = oper_inexact(opname, ltypeId, rtypeId))) + return (Operator) tup; + + if (!noError) op_error(opname, ltypeId, rtypeId); - return (Operator) tup; -} /* oper() */ + return (Operator) NULL; +} + +/* oper_oid() -- get OID of a binary operator + * + * This is a convenience routine that extracts only the operator OID + * from the result of oper(). InvalidOid is returned if the lookup + * fails and noError is true. + */ +Oid +oper_oid(char *op, Oid arg1, Oid arg2, bool noError) +{ + Operator optup; + Oid result; + optup = oper(op, arg1, arg2, noError); + if (optup != NULL) + { + result = oprid(optup); + ReleaseSysCache(optup); + return result; + } + return InvalidOid; +} /* unary_oper_get_candidates() * given opname, find all possible types for which @@ -671,8 +694,13 @@ unary_oper_get_candidates(char *opname, } /* unary_oper_get_candidates() */ -/* Given unary right-side operator (operator on right), return oper struct */ -/* arg-- type id */ +/* Given unary right operator (operator on right), return oper struct + * + * Always raises error on failure. + * + * NOTE: on success, the returned object is a syscache entry. The caller + * must ReleaseSysCache() the entry when done with it. + */ Operator right_oper(char *op, Oid arg) { @@ -682,11 +710,11 @@ right_oper(char *op, Oid arg) Oid *targetOid; /* Try for exact match */ - tup = SearchSysCacheTuple(OPERNAME, - PointerGetDatum(op), - ObjectIdGetDatum(arg), - ObjectIdGetDatum(InvalidOid), - CharGetDatum('r')); + tup = SearchSysCache(OPERNAME, + PointerGetDatum(op), + ObjectIdGetDatum(arg), + ObjectIdGetDatum(InvalidOid), + CharGetDatum('r')); if (!HeapTupleIsValid(tup)) { @@ -696,21 +724,21 @@ right_oper(char *op, Oid arg) unary_op_error(op, arg, FALSE); else if (ncandidates == 1) { - tup = SearchSysCacheTuple(OPERNAME, - PointerGetDatum(op), - ObjectIdGetDatum(candidates->args[0]), - ObjectIdGetDatum(InvalidOid), - CharGetDatum('r')); + tup = SearchSysCache(OPERNAME, + PointerGetDatum(op), + ObjectIdGetDatum(candidates->args[0]), + ObjectIdGetDatum(InvalidOid), + CharGetDatum('r')); } else { targetOid = oper_select_candidate(1, &arg, candidates); if (targetOid != NULL) - tup = SearchSysCacheTuple(OPERNAME, - PointerGetDatum(op), - ObjectIdGetDatum(targetOid[0]), - ObjectIdGetDatum(InvalidOid), - CharGetDatum('r')); + tup = SearchSysCache(OPERNAME, + PointerGetDatum(op), + ObjectIdGetDatum(targetOid[0]), + ObjectIdGetDatum(InvalidOid), + CharGetDatum('r')); } if (!HeapTupleIsValid(tup)) @@ -721,8 +749,13 @@ right_oper(char *op, Oid arg) } /* right_oper() */ -/* Given unary left-side operator (operator on left), return oper struct */ -/* arg--type id */ +/* Given unary left operator (operator on left), return oper struct + * + * Always raises error on failure. + * + * NOTE: on success, the returned object is a syscache entry. The caller + * must ReleaseSysCache() the entry when done with it. + */ Operator left_oper(char *op, Oid arg) { @@ -732,11 +765,11 @@ left_oper(char *op, Oid arg) Oid *targetOid; /* Try for exact match */ - tup = SearchSysCacheTuple(OPERNAME, - PointerGetDatum(op), - ObjectIdGetDatum(InvalidOid), - ObjectIdGetDatum(arg), - CharGetDatum('l')); + tup = SearchSysCache(OPERNAME, + PointerGetDatum(op), + ObjectIdGetDatum(InvalidOid), + ObjectIdGetDatum(arg), + CharGetDatum('l')); if (!HeapTupleIsValid(tup)) { @@ -746,21 +779,21 @@ left_oper(char *op, Oid arg) unary_op_error(op, arg, TRUE); else if (ncandidates == 1) { - tup = SearchSysCacheTuple(OPERNAME, - PointerGetDatum(op), - ObjectIdGetDatum(InvalidOid), - ObjectIdGetDatum(candidates->args[0]), - CharGetDatum('l')); + tup = SearchSysCache(OPERNAME, + PointerGetDatum(op), + ObjectIdGetDatum(InvalidOid), + ObjectIdGetDatum(candidates->args[0]), + CharGetDatum('l')); } else { targetOid = oper_select_candidate(1, &arg, candidates); if (targetOid != NULL) - tup = SearchSysCacheTuple(OPERNAME, - PointerGetDatum(op), - ObjectIdGetDatum(InvalidOid), - ObjectIdGetDatum(targetOid[0]), - CharGetDatum('l')); + tup = SearchSysCache(OPERNAME, + PointerGetDatum(op), + ObjectIdGetDatum(InvalidOid), + ObjectIdGetDatum(targetOid[0]), + CharGetDatum('l')); } if (!HeapTupleIsValid(tup)) @@ -778,24 +811,17 @@ left_oper(char *op, Oid arg) static void op_error(char *op, Oid arg1, Oid arg2) { - Type tp1 = NULL, - tp2 = NULL; - - if (typeidIsValid(arg1)) - tp1 = typeidType(arg1); - else + if (!typeidIsValid(arg1)) elog(ERROR, "Left hand side of operator '%s' has an unknown type" "\n\tProbably a bad attribute name", op); - if (typeidIsValid(arg2)) - tp2 = typeidType(arg2); - else + if (!typeidIsValid(arg2)) elog(ERROR, "Right hand side of operator %s has an unknown type" "\n\tProbably a bad attribute name", op); elog(ERROR, "Unable to identify an operator '%s' for types '%s' and '%s'" "\n\tYou will have to retype this query using an explicit cast", - op, typeTypeName(tp1), typeTypeName(tp2)); + op, typeidTypeName(arg1), typeidTypeName(arg2)); } /* unary_op_error() @@ -805,20 +831,14 @@ op_error(char *op, Oid arg1, Oid arg2) static void unary_op_error(char *op, Oid arg, bool is_left_op) { - Type tp1 = NULL; - - if (typeidIsValid(arg)) - tp1 = typeidType(arg); - else - { + if (!typeidIsValid(arg)) elog(ERROR, "Argument of %s operator '%s' has an unknown type" "\n\tProbably a bad attribute name", (is_left_op ? "left" : "right"), op); - } elog(ERROR, "Unable to identify a %s operator '%s' for type '%s'" "\n\tYou may need to add parentheses or an explicit cast", (is_left_op ? "left" : "right"), - op, typeTypeName(tp1)); + op, typeidTypeName(arg)); } |