(2012/03/15 0:29), Tom Lane wrote: > The posted patch for file_fdw takes the > approach of silently filtering out rows for which they're not true, > which is not obviously the right thing either --- quite aside from > whether that's a sane semantics, it's not going to scale to foreign key > constraints, and even for simple NOT NULL and CHECK constraints it > results in a runtime penalty on selects, which is not what people would > expect from a constraint.
I investigated DB2 a little bit. In DB2, the user can specify the VALIDATE_DATA_FILE option as a generic option for an external table attached to a data file, which specifies if the wrapper verifies that the data file is sorted. How about introducing this kind of option to file_fdw? It might be better that the default value for the option is 'false', and if the value is set to 'true', then file_fdw verifies NOT NULL, CHECK, and foreign key constraints. Best regards, Etsuro Fujita -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
