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Diffstat (limited to 'src/backend/optimizer/util/tlist.c')
| -rw-r--r-- | src/backend/optimizer/util/tlist.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/src/backend/optimizer/util/tlist.c b/src/backend/optimizer/util/tlist.c index 718057a773f..b8149f7b461 100644 --- a/src/backend/optimizer/util/tlist.c +++ b/src/backend/optimizer/util/tlist.c @@ -73,6 +73,35 @@ tlist_member_ignore_relabel(Node *node, List *targetlist) } /* + * tlist_member_match_var + * Same as above, except that we match the provided Var on the basis + * of varno/varattno/varlevelsup only, rather than using full equal(). + * + * This is needed in some cases where we can't be sure of an exact typmod + * match. It's probably a good idea to check the vartype anyway, but + * we leave it to the caller to apply any suitable sanity checks. + */ +TargetEntry * +tlist_member_match_var(Var *var, List *targetlist) +{ + ListCell *temp; + + foreach(temp, targetlist) + { + TargetEntry *tlentry = (TargetEntry *) lfirst(temp); + Var *tlvar = (Var *) tlentry->expr; + + if (!tlvar || !IsA(tlvar, Var)) + continue; + if (var->varno == tlvar->varno && + var->varattno == tlvar->varattno && + var->varlevelsup == tlvar->varlevelsup) + return tlentry; + } + return NULL; +} + +/* * flatten_tlist * Create a target list that only contains unique variables. * |