On 06/09/13 09:13, Szymon Guz wrote:
Hi, why isn't 'aa' always treated as string?
with x as ( select '1' a, '2' b ) SELECT levenshtein(a, b), length(a) FROM x; ERROR: failed to find conversion function from unknown to text
Why should I cast '1' to '1'::TEXT to satisfy a function (TEXT, TEXT)?
I think it's to do with the CTE. Presumably its types get fixed separately from the SELECT levenshtein() call. A quoted literal is type "unknown" until it has a context. It could be a date, point, hstore etc.
If you use the literals directly the context lets PostgreSQL figure it out. SELECT levenshtein('1','2'); -- Richard Huxton Archonet Ltd -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general