Обсуждение: Problems with PQfmod() returning -1 on varchar field (libpq-8.0.0 )?
Hi all, I've recently encountered a situation where PQfmod() fails to return the defined length of a varchar field referenced in a query, as expected - returning no information (-1), instead. Has anyone else encountered this issue? If so, why does this occur? Can you recommended a method to more reliably obtain the length of varchar fields, as defined in the relations referenced by a query? Thanks, Jerry L. Day
Jerry Day wrote: > Hi all, > > I've recently encountered a situation where PQfmod() fails to return the > defined length of a varchar field referenced in a query, as expected - > returning no information (-1), instead. Has anyone else encountered this > issue? If so, why does this occur? Can you recommended a method to more > reliably obtain the length of varchar fields, as defined in the relations > referenced by a query? Can we see the query? I suspect the column is being manipulated in some way and the length isn't carried through to the query output --- if so, there might not be much we can do about it. -- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610) 359-1001+ If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania19073
On Fri, Apr 01, 2005 at 04:21:03PM -0800, Jerry Day wrote: > > I've recently encountered a situation where PQfmod() fails to return the > defined length of a varchar field referenced in a query, as expected - > returning no information (-1), instead. Has anyone else encountered this > issue? If so, why does this occur? Can you recommended a method to more > reliably obtain the length of varchar fields, as defined in the relations > referenced by a query? Are you sure the column has a length specifier? What does "\d tablename" show, or what's the result of the following query? SELECT attname, attnum, atttypid::regtype, atttypmod FROM pg_attribute WHERE attrelid = 'tablename'::regclass AND attnum >= 1 AND attisdropped IS FALSE ORDER by attnum; -- Michael Fuhr http://www.fuhr.org/~mfuhr/