diff options
Diffstat (limited to 'src/backend/optimizer/util/keys.c')
| -rw-r--r-- | src/backend/optimizer/util/keys.c | 261 |
1 files changed, 134 insertions, 127 deletions
diff --git a/src/backend/optimizer/util/keys.c b/src/backend/optimizer/util/keys.c index 4296deb7e98..0c3a3569eb5 100644 --- a/src/backend/optimizer/util/keys.c +++ b/src/backend/optimizer/util/keys.c @@ -1,13 +1,13 @@ /*------------------------------------------------------------------------- * * keys.c-- - * Key manipulation routines + * Key manipulation routines * * Copyright (c) 1994, Regents of the University of California * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/optimizer/util/Attic/keys.c,v 1.2 1997/08/19 21:32:03 momjian Exp $ + * $Header: /cvsroot/pgsql/src/backend/optimizer/util/Attic/keys.c,v 1.3 1997/09/07 04:44:28 momjian Exp $ * *------------------------------------------------------------------------- */ @@ -22,173 +22,180 @@ #include "optimizer/tlist.h" -static Expr *matching2_tlvar(int var, List *tlist, bool (*test)()); -static bool equal_indexkey_var(int index_key, Var *var); +static Expr *matching2_tlvar(int var, List * tlist, bool(*test) ()); +static bool equal_indexkey_var(int index_key, Var * var); -/* +/* * 1. index key - * one of: - * attnum - * (attnum arrayindex) + * one of: + * attnum + * (attnum arrayindex) * 2. path key - * (subkey1 ... subkeyN) - * where subkeyI is a var node - * note that the 'Keys field is a list of these + * (subkey1 ... subkeyN) + * where subkeyI is a var node + * note that the 'Keys field is a list of these * 3. join key - * (outer-subkey inner-subkey) - * where each subkey is a var node + * (outer-subkey inner-subkey) + * where each subkey is a var node * 4. sort key - * one of: - * SortKey node - * number - * nil - * (may also refer to the 'SortKey field of a SortKey node, - * which looks exactly like an index key) - * + * one of: + * SortKey node + * number + * nil + * (may also refer to the 'SortKey field of a SortKey node, + * which looks exactly like an index key) + * */ -/* +/* * match-indexkey-operand-- - * Returns t iff an index key 'index-key' matches the given clause - * operand. - * + * Returns t iff an index key 'index-key' matches the given clause + * operand. + * */ bool -match_indexkey_operand(int indexkey, Var *operand, Rel *rel) +match_indexkey_operand(int indexkey, Var * operand, Rel * rel) { - if (IsA (operand,Var) && - (lfirsti(rel->relids) == operand->varno) && - equal_indexkey_var(indexkey,operand)) - return(true); - else - return(false); + if (IsA(operand, Var) && + (lfirsti(rel->relids) == operand->varno) && + equal_indexkey_var(indexkey, operand)) + return (true); + else + return (false); } -/* +/* * equal_indexkey_var-- - * Returns t iff an index key 'index-key' matches the corresponding - * fields of var node 'var'. - * + * Returns t iff an index key 'index-key' matches the corresponding + * fields of var node 'var'. + * */ -static bool -equal_indexkey_var(int index_key, Var *var) +static bool +equal_indexkey_var(int index_key, Var * var) { - if (index_key == var->varattno) - return(true); - else - return(false); + if (index_key == var->varattno) + return (true); + else + return (false); } -/* +/* * extract-subkey-- - * Returns the subkey in a join key corresponding to the outer or inner - * lelation. - * + * Returns the subkey in a join key corresponding to the outer or inner + * lelation. + * */ -Var * -extract_subkey(JoinKey *jk, int which_subkey) +Var * +extract_subkey(JoinKey * jk, int which_subkey) { - Var *retval; - - switch (which_subkey) { - case OUTER: - retval = jk->outer; - break; - case INNER: - retval = jk->inner; - break; - default: /* do nothing */ - elog(DEBUG,"extract_subkey with neither INNER or OUTER"); - retval = NULL; - } - return(retval); + Var *retval; + + switch (which_subkey) + { + case OUTER: + retval = jk->outer; + break; + case INNER: + retval = jk->inner; + break; + default: /* do nothing */ + elog(DEBUG, "extract_subkey with neither INNER or OUTER"); + retval = NULL; + } + return (retval); } -/* +/* * samekeys-- - * Returns t iff two sets of path keys are equivalent. They are - * equivalent if the first subkey (var node) within each sublist of - * list 'keys1' is contained within the corresponding sublist of 'keys2'. - * - * XXX It isn't necessary to check that each sublist exactly contain - * the same elements because if the routine that built these - * sublists together is correct, having one element in common - * implies having all elements in common. - * + * Returns t iff two sets of path keys are equivalent. They are + * equivalent if the first subkey (var node) within each sublist of + * list 'keys1' is contained within the corresponding sublist of 'keys2'. + * + * XXX It isn't necessary to check that each sublist exactly contain + * the same elements because if the routine that built these + * sublists together is correct, having one element in common + * implies having all elements in common. + * */ bool -samekeys(List *keys1, List *keys2) +samekeys(List * keys1, List * keys2) { - bool allmember = true; - List *key1, *key2; - - for(key1=keys1,key2=keys2 ; key1 != NIL && key2 !=NIL ; - key1=lnext(key1), key2=lnext(key2)) - if (!member(lfirst(key1), lfirst(key2))) - allmember = false; - - if ( (length (keys2) >= length (keys1)) && allmember) - return(true); - else - return(false); + bool allmember = true; + List *key1, + *key2; + + for (key1 = keys1, key2 = keys2; key1 != NIL && key2 != NIL; + key1 = lnext(key1), key2 = lnext(key2)) + if (!member(lfirst(key1), lfirst(key2))) + allmember = false; + + if ((length(keys2) >= length(keys1)) && allmember) + return (true); + else + return (false); } -/* +/* * collect-index-pathkeys-- - * Creates a list of subkeys by retrieving var nodes corresponding to - * each index key in 'index-keys' from the relation's target list - * 'tlist'. If the key is not in the target list, the key is irrelevant - * and is thrown away. The returned subkey list is of the form: - * ((var1) (var2) ... (varn)) - * + * Creates a list of subkeys by retrieving var nodes corresponding to + * each index key in 'index-keys' from the relation's target list + * 'tlist'. If the key is not in the target list, the key is irrelevant + * and is thrown away. The returned subkey list is of the form: + * ((var1) (var2) ... (varn)) + * * 'index-keys' is a list of index keys * 'tlist' is a relation target list - * + * * Returns the list of cons'd subkeys. - * + * */ /* This function is identical to matching_tlvar and tlistentry_member. * They should be merged. */ -static Expr * -matching2_tlvar(int var, List *tlist, bool (*test)()) +static Expr * +matching2_tlvar(int var, List * tlist, bool(*test) ()) { - TargetEntry *tlentry = NULL; - - if (var) { - List *temp; - foreach (temp,tlist) { - if ((*test)(var, get_expr(lfirst(temp)))) { - tlentry = lfirst(temp); - break; - } + TargetEntry *tlentry = NULL; + + if (var) + { + List *temp; + + foreach(temp, tlist) + { + if ((*test) (var, get_expr(lfirst(temp)))) + { + tlentry = lfirst(temp); + break; + } + } } - } - if (tlentry) - return((Expr*)get_expr(tlentry)); - else - return((Expr*)NULL); + if (tlentry) + return ((Expr *) get_expr(tlentry)); + else + return ((Expr *) NULL); } -List * -collect_index_pathkeys(int *index_keys, List *tlist) +List * +collect_index_pathkeys(int *index_keys, List * tlist) { - List *retval = NIL; - - Assert (index_keys != NULL); - - while(index_keys[0] != 0) { - Expr *mvar; - mvar = matching2_tlvar(index_keys[0], - tlist, - equal_indexkey_var); - if (mvar) - retval = nconc(retval,lcons(lcons(mvar,NIL), - NIL)); - index_keys++; - } - return(retval); -} + List *retval = NIL; + + Assert(index_keys != NULL); + + while (index_keys[0] != 0) + { + Expr *mvar; + mvar = matching2_tlvar(index_keys[0], + tlist, + equal_indexkey_var); + if (mvar) + retval = nconc(retval, lcons(lcons(mvar, NIL), + NIL)); + index_keys++; + } + return (retval); +} |