How to delete data from multiple tables?

Question

I have these tables:

event     (evt_id, evt_code, reg_id)

magnitude (mag_id, evt_id, value)

trace     (trace_id, pt_id)

point     (         


        

Answer 1

I assume that the id's in the different tables correspond and are used for linking. I also assume you want to delete all the trace points allthough they are only indirectly linked to evt_id

You can delete your records from all tables as follows:

DELETE event , magnitude, trace, point
FROM event left join magnitude on event.evt_id = magnitude.evt_id
   left join point on event.evt_id = point.evt_id
       left join trace on point.pt_id = trace.trace_id
where event_id=1139