database - SQL - field involving multiple rows from another table -


what i'm trying figure out surely answered before, can't find here (since i'm not sure should search for), bare me.

i have created/am creating 3 tables: slaves, citizens , incidents.

how should go incident involving multiple citizens , slaves? i'm thinking making 2 fields in incidents containing list of citizenid's , slaveid's (slaveid1, slaveid2...,slaveidn), seems plain dumb.

actually idea doesn't sound dumb @ all. can design incidents table this:

+------------+-----------+---------+ | incidentid | citizenid | slaveid | +------------+-----------+---------+ |     1      |         |       |      <-- incident #1 involved 2 citizens , 1 slave |     1      |     b     |       | |     2      |         |       |      <-- incident #2 involved 2 citizens , 2 slaves |     2      |     b     |       | |     2      |         |    b    | |     2      |         |    b    | +------------+-----------+---------+

now when query incident id can obtain list of citizens , slaves involved in incident. many-to-many relationship in database schema.


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