I do not know, but I did some internet research and found the following: *PostgreSQL*: supports POSIX style regexps, described to great detail in: http://www.postgresql.org/docs/9.0/static/functions-matching.html *MySQL*: supports a style "which is aimed at conformance with POSIX 1003.2", described here: http://dev.mysql.com/doc/refman/5.1/en/regexp.html *Oracle*: supports "IEEE Portable Operating System Interface (POSIX) standard draft 1003.2/D11.2", described: http://docs.oracle.com/cd/B19306_01/appdev.102/b14251/adfns_regexp.htm *MSSQL*: not sure, I think you probably need to define a function on your own using CLR language (?). *FireBird*: Support RegExp, but didn't specify according to which syntax exactly. Details: http://www.firebirdsql.org/rlsnotesh/rlsnotes25.html#rnfb25-dml-regex *DB2*: Need to implement a function that does it, details: http://www.ibm.com/developerworks/data/library/techarticle/0301stolze/0301stolze.html *Informix, Ingres*: Not sure, wasn't able to find something definitive, but probably need to extend the language to support regexps.
In addition I found the following article of someone who explored the regexp support of popular SQL databases: http://trentrichardson.com/2008/10/23/exploring-various-sql-regex-syntax/ All in all, seems that most systems support some version of POSIX standard, except when you need to extend the SQL with a user defined function, then I guess you can chose the implementation you want. Hope this help, Omri
