如何过滤MySQL数据库中的项目列表？

I have list store in mysql table file1=(1,2,3,4,6,7) and other list file2 = (3,2,4,8,9,10,12) is not stored in table, i want compare both and result should be like result=(6,7,8,9,10,12) then calculate the percentage. like 100*(result/file1+file2) in mysql data structure. i do not know how i will do it. please know body know guide me or give me a small example. thanks I have list store in mysql table file1=(1,2,3,4