Install php-mysql and mysql-server. This will install all necessary dependencies, including php, libiconv and several perl modules needed by the MySQL scripts.
$ sudo pkg_add php-mysql mysql-server
Ambiguous: choose package for php-mysql
a 0:
1: php-mysql-5.2.17p16
2: php-mysql-5.3.27
Your choice: 2
Ambiguous: choose dependency for php-mysql-5.3.27:
a 0: php-5.3.27
1: php-5.3.27-ap2
Your choice: 0
REF: http://www.h-i-r.net/p/hirs-secure-openbsd-apache-mysql-and.html
