Mysql using like with two variables in different tabel
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I have two tables a and b.`Table a` has a field named `gr` which can have multiple values concatinted with string.`Table b` holds it seperately in fields `lg`.How do i run the below query to check wheather `b.lg` is ther in `a.gr`
  

     SELECT lg FROM `a`,`b` WHERE a.`id` =22 AND  (a.gr LIKE '%'+b.lg+'%')