Mysql Merging Databases - Same Schema -

so year ago have taken on development , management of database organisation work for. (in-house developer).

the organisation national organisation, started out in 1 state. dev company in charge of development @ time, decided take shortcut method of opening database other state duplicating schema , putting under different name.

so, left work 4 duplicate database, years of information in them can't lose.

it largely acts training database. site has classes, people participant in classes, there links cant messed up.

site: (ai)site_id  classes: (ai)class_id site_id  person: (ai)person_id  participants: (ai)id person_id site_id 

of course, 1 small part of database.

i wanting turn partial tennant based database, can separate information needs separating (classes, sites ect), , national information (like person person in state) global.

site: (ai)site_id state_id  classes: (ai)class_id site_id state_id  person: person_id  participants: (ai)id person_id class_id state_id 

i hoping has been in similar situation , might able offer advice or guidance, or perhaps suggest tool facilitate change.