Scalar. Returns the first occurrence of a POSIX regular expression pattern found in a given string.
regexp_firstsearch ( string, regex )
| string | A string. |
| regex | A POSIX regular expression pattern. This pattern is limited to the Perl syntax. |
Returns the first occurrence of a POSIX regular expression pattern found in a given string. If string does not contain a match for the pattern, or if the specified pattern is not a valid regular expression, the function returns NULL. One or more subexpressions can be included in the pattern, each enclosed in parentheses. If string contains a match for the pattern, the function only returns the parts of the pattern specified by the first subexpression. The function returns a string.
The function works with UTF-8 strings if the -U server option is specified.
regexp_firstsearch('aaadogaaa', '[b-z]*') returns 'dog'.
regexp_firstsearch('h', '[i-z]*') returns NULL.
regexp_firstsearch('aaaaabaaaabbbaaa', '[b-z]*') returns 'b'.