Don't do it: reorganise your database to include an extra table so that you don't use comma separated data in your table: it's nice and easy to add the data, but everything else is a PITA.
You can do what you want; it's a pain but you can
Converting comma separated data in a column to rows for selection[
^]
But that is something you have to do every time you need to deal with the data. And have you considered how you will remove one of the comma separated values? Or find the right one?
Change your DB now, while it's still easy to do: you are building up a whole pile of problems for yourself in future, and the later you leave it, the more hassle it is to change!
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