How can I split comma separated value in MySQL into rows?

Question

I have a function in MySQL that returns a list of integer values separated by a comma, thus forming a string.

e.g.

MyFunction(23);

Ret

Answer 1

You can use FIND_IN_SET function. For example:

SELECT FIND_IN_SET('34', '34,45,87,23,1'); -- return true

SELECT FIND_IN_SET('34', '34'); -- return true    

SELECT FIND_IN_SET('34', ''); -- return false

In your case, the SQL query will look like:

SELECT id,
       myItemId,
       myItemValue,
       myDateTime
FROM items
WHERE id IN
    (SELECT MAX(id)
     FROM items
     WHERE myItemId=1
       AND FIND_IN_SET(myItemValue, MyFunction(123))
     GROUP BY myItemId);