I need to create some indexes on some mysql fields. One of them is of type SET. I remember reading somewhere that these are bad for indexes and I should convert them to another type. Is this correct? They are text values so should I convert them to CHAR, TEXT or ENUM?
I also have some other fields of type CHAR which only take a fixed set of values. Should I convert these to ENUM before i make them into indexes?
Thanks in advance for your help