difference between where_in and find_in_set

Question

I am working on a join query in which I have to get the data from a column which contain the comma separated values.like allowed_activity contain 1,2,3,4,5,6<

Answer 1

FIND_IN_SET search for a value in a array and return the index of the value then if the function is different than 0 this mean that the value in present in the list . so the code

  this->db->where("FIND_IN_SET(6, a.allowed_activity) !=",0);

mean return the index of the value 6 in a.allowed_activity
and if the value return is different that 0 then the value 6 is present in a.allowed_activity

WHERE ... IN check if the value in the set but don't return the index .. just return true or false if the value is present or not