Re: (PATCH) Adding CORRESPONDING (NULL error) - Mailing list pgsql-hackers

(pgsql 9.2devel (25 oct) with your latest CORRESPONDING patch;
linux x86_64 GNU/Linux 2.6.18-274.3.1.el5)

Hi,

here is another peculiarity, which I think is a bug:

-- first without CORRESPONDING:

$ psql -Xaf null.sql           select 1 a   , 2 b
union all           select null a, 4 b ;a | b
---+---1 | 2  | 4
(2 rows)

-- then with CORRESPONDING:
           select 1 a   , 2 b
union all
corresponding           select null a, 4 b ;
psql:null.sql:9: ERROR:  failed to find conversion function from unknown to integer


If the null value is in a table column the error does not occur:

drop table if exists t1; create table t1 (a int, b int); insert into t1 values (1,2);
drop table if exists t2; create table t2 (a int, b int); insert into t2 values (null,2);               select a,b from
t1
union all
corresponding               select a,b from t2 ;a | b
---+---1 | 2  | 2
(2 rows)


I'm not sure it is actually a bug; but it seems an unneccessary error.


thanks,

Erik Rijkers