diff options
| author | Tom Lane | 2014-01-09 01:18:06 +0000 |
|---|---|---|
| committer | Tom Lane | 2014-01-09 01:18:58 +0000 |
| commit | 080b7db72ebbec22580237631d6b07d0e1147b01 (patch) | |
| tree | 756ffb242ae077c408e04889810d1b0b0adbcdfe /src/test | |
| parent | daa7527afc2274432094ebe7ceb03aa41f916607 (diff) | |
Fix "cannot accept a set" error when only some arms of a CASE return a set.
In commit c1352052ef1d4eeb2eb1d822a207ddc2d106cb13, I implemented an
optimization that assumed that a function's argument expressions would
either always return a set (ie multiple rows), or always not. This is
wrong however: we allow CASE expressions in which some arms return a set
of some type and others just return a scalar of that type. There may be
other examples as well. To fix, replace the run-time test of whether an
argument returned a set with a static precheck (expression_returns_set).
This adds a little bit of query startup overhead, but it seems barely
measurable.
Per bug #8228 from David Johnston. This has been broken since 8.0,
so patch all supported branches.
Diffstat (limited to 'src/test')
| -rw-r--r-- | src/test/regress/expected/rangefuncs.out | 14 | ||||
| -rw-r--r-- | src/test/regress/sql/rangefuncs.sql | 9 |
2 files changed, 23 insertions, 0 deletions
diff --git a/src/test/regress/expected/rangefuncs.out b/src/test/regress/expected/rangefuncs.out index a988dd01a12..9d40510ecdb 100644 --- a/src/test/regress/expected/rangefuncs.out +++ b/src/test/regress/expected/rangefuncs.out @@ -1992,3 +1992,17 @@ select * from foobar(); -- fail ERROR: function return row and query-specified return row do not match DETAIL: Returned row contains 3 attributes, but query expects 2. drop function foobar(); +-- check behavior when a function's input sometimes returns a set (bug #8228) +SELECT *, + lower(CASE WHEN id = 2 THEN (regexp_matches(str, '^0*([1-9]\d+)$'))[1] + ELSE str + END) +FROM + (VALUES (1,''), (2,'0000000049404'), (3,'FROM 10000000876')) v(id, str); + id | str | lower +----+------------------+------------------ + 1 | | + 2 | 0000000049404 | 49404 + 3 | FROM 10000000876 | from 10000000876 +(3 rows) + diff --git a/src/test/regress/sql/rangefuncs.sql b/src/test/regress/sql/rangefuncs.sql index ac2769fdba9..07d2e1a490e 100644 --- a/src/test/regress/sql/rangefuncs.sql +++ b/src/test/regress/sql/rangefuncs.sql @@ -599,3 +599,12 @@ $$ select (1, 2.1, 3) $$ language sql; select * from foobar(); -- fail drop function foobar(); + +-- check behavior when a function's input sometimes returns a set (bug #8228) + +SELECT *, + lower(CASE WHEN id = 2 THEN (regexp_matches(str, '^0*([1-9]\d+)$'))[1] + ELSE str + END) +FROM + (VALUES (1,''), (2,'0000000049404'), (3,'FROM 10000000876')) v(id, str); |