MySQL-基于另一个列值的单个列中有多个唯一集

Question

I must create a table for handling student data which has two columns department code and register number ,. For Eg. dept 101 has 30 students with register numbers (1-30) And dept 102 has 30 different students with same register numbers (1-30) . for instance.,The student with regno:3 who belongs to dept:101 and another student with regno:3 but in the dept:102 are in same table.,There can be same regno's but different dept code is there a way to relate my two columns.. I have added another image for more clarifications Table Structure with data My problem is how can i have unique set register numbers for each deparment in the same column to avoid duplication . The Values of reg_no with same Department Code must have a unique set,.. and another set of regno with a different dept_code must have another or individual set of unique set of numbers Can i Have Multiple unique sets in a single Column..?? The Table sample image

Is there any solution or should i use another table for each dept_code

Tried on Googling didn't Get a result yet . Thanks in Advance

Answer 1

try this

UNIQUE KEY 'thekey' ('dept','regno');

more about the background is found at this StackOverflow post