Compare two tables and generate one piechart

Migrateduser

<p>Hello everyone. I have a question. There are two tables in my database. They are totally same in the table structure. Suppose table A and B. They have two field, the name is c and d. I want to get the number of A.c>B.c, A.c<B.c and A.c=B.c. Then generate a piechart that display the better, worse, same percentage.</p>