FULL OUTER JOIN With MySQL, MySQL don't support ist what is the solution for more than 2 Tables?
Build a VIEW that simulates a FULL OUTER JOIN of A and B.  (Use the template given by some of the links.)
Build a VIEW that simulates a FULL OUTER JOIN of that VIEW and C.  (Use the template given by some of the links.)
Etc.


Eventually, you will have a FULL OUTER JOIN of all the tables without the ugly mess of compounding the number of joins needed.