Syntax:
expr REGEXP pat expr RLIKE pat

Performs a pattern match of a string expression expr against a pattern
pat. The pattern can be an extended regular expression. The syntax for
regular expressions is discussed in
http://dev.mysql.com/doc/refman/4.1/en/regexp.html. Returns 1 if expr
matches pat; otherwise it returns 0. If either expr or pat is NULL, the
result is NULL. RLIKE is a synonym for REGEXP, provided for mSQL
compatibility.

The pattern need not be a literal string. For example, it can be
specified as a string expression or table column.

Note: Because MySQL uses the C escape syntax in strings (for example,
`\n' to represent the newline character), you must double any `\' that
you use in your REGEXP strings.

As of MySQL 3.23.4, REGEXP is not case sensitive, except when used with
binary strings.
