I'm doing a check within a PL/PGSQL function using a regular expression and I get the error: ERROR: regcomp failed with error invalid character range This appears to be because of the underscore "_" character. The regex I want to use is ''[A-Za-z0-9_]'' but this doesn't work. Any suggestions or is this a bug/feature? ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/users-lounge/docs/faq.html