Re: (PATCH) Adding CORRESPONDING (NULL error)

(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