diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/parser/parse_coerce.c | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/src/backend/parser/parse_coerce.c b/src/backend/parser/parse_coerce.c index ef13d67cf1c..f0d3427d17e 100644 --- a/src/backend/parser/parse_coerce.c +++ b/src/backend/parser/parse_coerce.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/parser/parse_coerce.c,v 2.47 2000/10/05 19:11:33 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/parser/parse_coerce.c,v 2.48 2000/11/09 04:14:32 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -374,6 +374,22 @@ select_common_type(List *typeids, const char *context) } } } + + /* + * If all the inputs were UNKNOWN type --- ie, unknown-type literals --- + * then resolve as type TEXT. This situation comes up with constructs + * like + * SELECT (CASE WHEN foo THEN 'bar' ELSE 'baz' END); + * SELECT 'foo' UNION SELECT 'bar'; + * It might seem desirable to leave the construct's output type as + * UNKNOWN, but that really doesn't work, because we'd probably end up + * needing a runtime coercion from UNKNOWN to something else, and we + * usually won't have it. We need to coerce the unknown literals while + * they are still literals, so a decision has to be made now. + */ + if (ptype == UNKNOWNOID) + ptype = TEXTOID; + return ptype; } |