Feature: implement database subseting for MySQL

[evoxmusic]

Implement database subsetting for MySQL as we did for PostgreSQL.

[fabriceclementz]

Hi @benny-n

I looked at the dump_header and dump_footer functions and they can't work with MySQL as the dump format is not the same as for PostgreSQL.

In Postgres, we have all the CREATE TABLE statement first, then INSERT INTO and ALTER TABLE.

For MySQL, we have:

• CREATE TABLE (which contains the constraints to extract from which we can extract foreign keys)
• INSERT INTO corresponding to the precedent table and so on

Maybe one possible solution that might work could be to extract only the database structure first via mysqldump --no-data ... and then make the full dump and add the INSERT INTO statement at the end of the previously created dump?

There may be a better solution but I have no other idea at the moment.