diff options
Diffstat (limited to 'src/backend/parser/parse_oper.c')
| -rw-r--r-- | src/backend/parser/parse_oper.c | 69 |
1 files changed, 31 insertions, 38 deletions
diff --git a/src/backend/parser/parse_oper.c b/src/backend/parser/parse_oper.c index fd41f4f3a0f..2a9de556b26 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 1.39 2000/03/19 00:19:39 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/parser/parse_oper.c,v 1.40 2000/04/12 17:15:27 momjian Exp $ * *------------------------------------------------------------------------- */ @@ -29,10 +29,10 @@ static Oid *oper_select_candidate(int nargs, Oid *input_typeids, static Operator oper_exact(char *op, Oid arg1, Oid arg2); static Operator oper_inexact(char *op, Oid arg1, Oid arg2); static int binary_oper_get_candidates(char *opname, - CandidateList *candidates); + CandidateList *candidates); static int unary_oper_get_candidates(char *opname, - CandidateList *candidates, - char rightleft); + CandidateList *candidates, + char rightleft); static void op_error(char *op, Oid arg1, Oid arg2); static void unary_op_error(char *op, Oid arg, bool is_left_op); @@ -229,8 +229,8 @@ oper_select_candidate(int nargs, return candidates->args; /* - * Run through all candidates and keep those with the most matches - * on exact types. Keep all candidates if none match. + * Run through all candidates and keep those with the most matches on + * exact types. Keep all candidates if none match. */ ncandidates = 0; nbestMatch = 0; @@ -273,10 +273,9 @@ oper_select_candidate(int nargs, return candidates->args; /* - * Still too many candidates? - * Run through all candidates and keep those with the most matches - * on exact types + binary-compatible types. - * Keep all candidates if none match. + * Still too many candidates? Run through all candidates and keep + * those with the most matches on exact types + binary-compatible + * types. Keep all candidates if none match. */ ncandidates = 0; nbestMatch = 0; @@ -323,10 +322,9 @@ oper_select_candidate(int nargs, return candidates->args; /* - * Still too many candidates? - * Now look for candidates which are preferred types at the args that - * will require coercion. - * Keep all candidates if none match. + * Still too many candidates? Now look for candidates which are + * preferred types at the args that will require coercion. Keep all + * candidates if none match. */ ncandidates = 0; nbestMatch = 0; @@ -370,15 +368,16 @@ oper_select_candidate(int nargs, return candidates->args; /* - * Still too many candidates? - * Try assigning types for the unknown columns. + * Still too many candidates? Try assigning types for the unknown + * columns. * * First try: if we have an unknown and a non-unknown input, see whether - * there is a candidate all of whose input types are the same as the known - * input type (there can be at most one such candidate). If so, use that - * candidate. NOTE that this is cool only because operators can't - * have more than 2 args, so taking the last non-unknown as current_type - * can yield only one possibility if there is also an unknown. + * there is a candidate all of whose input types are the same as the + * known input type (there can be at most one such candidate). If so, + * use that candidate. NOTE that this is cool only because operators + * can't have more than 2 args, so taking the last non-unknown as + * current_type can yield only one possibility if there is also an + * unknown. */ unknownOids = FALSE; current_type = UNKNOWNOID; @@ -410,16 +409,16 @@ oper_select_candidate(int nargs, } /* - * Second try: examine each unknown argument position to see if all the - * candidates agree on the type category of that slot. If so, and if some - * candidates accept the preferred type in that category, eliminate the - * candidates with other input types. If we are down to one candidate - * at the end, we win. + * Second try: examine each unknown argument position to see if all + * the candidates agree on the type category of that slot. If so, and + * if some candidates accept the preferred type in that category, + * eliminate the candidates with other input types. If we are down to + * one candidate at the end, we win. * * XXX It's kinda bogus to do this left-to-right, isn't it? If we - * eliminate some candidates because they are non-preferred at the first - * slot, we won't notice that they didn't have the same type category for - * a later slot. + * eliminate some candidates because they are non-preferred at the + * first slot, we won't notice that they didn't have the same type + * category for a later slot. */ for (i = 0; i < nargs; i++) { @@ -472,7 +471,7 @@ oper_select_candidate(int nargs, last_candidate = current_candidate; } } - if (last_candidate) /* terminate rebuilt list */ + if (last_candidate) /* terminate rebuilt list */ last_candidate->next = NULL; } } @@ -588,9 +587,7 @@ oper(char *opname, Oid ltypeId, Oid rtypeId, bool noWarnings) { } else if (!noWarnings) - { op_error(opname, ltypeId, rtypeId); - } return (Operator) tup; } /* oper() */ @@ -679,14 +676,12 @@ right_oper(char *op, Oid arg) /* Try for inexact matches */ ncandidates = unary_oper_get_candidates(op, &candidates, 'r'); if (ncandidates == 0) - { unary_op_error(op, arg, FALSE); - } else if (ncandidates == 1) { tup = SearchSysCacheTuple(OPERNAME, PointerGetDatum(op), - ObjectIdGetDatum(candidates->args[0]), + ObjectIdGetDatum(candidates->args[0]), ObjectIdGetDatum(InvalidOid), CharGetDatum('r')); } @@ -731,15 +726,13 @@ left_oper(char *op, Oid arg) /* Try for inexact matches */ ncandidates = unary_oper_get_candidates(op, &candidates, 'l'); if (ncandidates == 0) - { unary_op_error(op, arg, TRUE); - } else if (ncandidates == 1) { tup = SearchSysCacheTuple(OPERNAME, PointerGetDatum(op), ObjectIdGetDatum(InvalidOid), - ObjectIdGetDatum(candidates->args[0]), + ObjectIdGetDatum(candidates->args[0]), CharGetDatum('l')); } else |