mysql - sql more than one keys in one field -

i guess, name of question strange, don't know how state correctly, i'll try describe problem. say, have 2 tables:

1)

id | unit_name | strength | health 1  | private   | 10       | 10 2  | general   | 5        | 5 n  |   | 123      | 321 

2)

id | rules | who_has_this_rule 1  | rule1 | 1 2  | rule2 | 2 3  | rule3 | 1 4  | rule4 | 1 

the field "who_has_this_rule" correspondes id of first table. can't figure out if unit should have more 1 rule in profile. example, private should have rule1 , rule4. how this?

what need join table.

a third table join rule , units

unit_rules

id | unit_id | rule_id 1  |  1      | 1 2  |  1      | 4 3  |  2      | 1 

you can have primary key(id) or compound key(unit_id , rule_id)