Why not to use information schema:
select column_name, character_maximum_length from information_schema.columns where table_name ='table name'
09.09.2011, 16:53, "shuaixf" <shuaixf@gmail.com>:
> SELECT a.attname, pg_catalog.format_type(a.atttypid, a.atttypmod)
> FROM pg_catalog.pg_attribute a
> WHERE a.attrelid = (SELECT pg_class.oid
> FROM pg_class INNER JOIN pg_namespace
> ON (pg_class.relnamespace = pg_namespace.oid
> AND lower(pg_namespace.nspname) = 'public')
> WHERE pg_class.relname='tablename')
> AND a.attnum > 0 AND NOT a.attisdropped
> ORDER BY a.attnum;
>
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