How to convert PostgreSQL to MySQL
Use following command to get the backup data. 

pg_dump --inserts -f filename.dump your_database


This commands generates the sql script that can be used to restore schema as well as data to other sql databases. The --inserts options tells it to use inserts instead of default copy commands. 

Here is the manual - http://www.postgresql.org/docs/current/interactive/app-pgdump.html