テーブルのカラム名と型名をとってくる。
SELECT pg_attribute.attname, pg_type.typname, pg_attribute.attlen FROM pg_attribute, pg_type WHERE pg_attribute.atttypid = pg_type.oid AND ( pg_attribute.atttypid < 26 OR pg_attribute.atttypid > 29 ) AND attrelid IN ( SELECT pg_class.oid FROM pg_class, pg_namespace WHERE relname='__TABLE_NAME__' AND pg_class.relnamespace=pg_namespace.oid AND pg_namespace.nspname='__SCHEMA_NAME__' );