The following bug has been logged online: Bug reference: 5469 Logged by: Daniele Varrazzo Email address: daniele.varra...@gmail.com PostgreSQL version: 8.4 Operating system: any Description: regexp_matches() has poor behaviour and more poor documentation Details:
regexp_matches() has been recently discussed (http://archives.postgresql.org/pgsql-bugs/2010-04/msg00026.php): it is a setof function and as such it can drop results. Unfortunately it is an useful function to newcomers who use SQL, use regexps but don't arrive to read the chapter 34.4.7. (i.e. Extending SQL -> Query Language (SQL) Functions -> SQL Functions Returning Sets) and are not so enlightened to know that "setof text[]" means "if it doesn't match, it drops the record". They just expect the function to be a LIKE on steroids. Please describe the behavior in the documentation of the function (i.e. table 9-6. and section 9.7.3), possibly provide a function with a saner interface, i.e. returning a text[] of the first match or NULL on no match, or document a workaround (suitable for an user knowing regexps but not setof-returning functions) to make the function not dropping record (e.g. I fixed the "bug" adding a "|" at the end of the pattern, so that the function returns an array of NULL in case of no match: I don't think it is a trivial workaround). -- Sent via pgsql-bugs mailing list (pgsql-bugs@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-bugs
