insert multiple data in a single field using separator

Question

Hi,

 

In my project I have one topic and related to that i have multiple questions.

ex: topic question

        t1       q1

         t1       q2

        t1        q3

currently i am storing  data in database like:

 

topic  question

t1       q1

t1       q2

t1       q3 

but i want like this:

 

topic     question

t1             q1,q2,q3

 

please help me..