Re: Check type compatibility

Hello,
I believe types are compatible if they can be cast automatically.
The pg_cast table record all possible casts between types. If it castcontext is 'a' then I belive it's an automatic conversion which is what I think you want. 'i' implicit means that cast is possible, but must be explicitly cast.

I suspect that you'll need to write a function that consults the table for the type pair.

Cheers
Doug

-----Original Message-----
From: pgsql-sql-owner(at)postgresql(dot)org [mailto:pgsql-sql-owner(at)postgresql(dot)org] On Behalf Of Gianvito Pio
Sent: Saturday, March 06, 2010 5:04 AM
To: pgsql-sql(at)postgresql(dot)org
Subject: [SQL] Check type compatibility

Hi all,
is there a way to check if two attribute are type compatible (for
example integer and serial, integer and integer, character varying and
text, etc..)?

Example:
IF (compatible (table1.att1, table2.att2)) THEN
...
ELSE
...
END IF;

Thanks