How can I avoid a full table scan on this mysql query?

Question

explain
select
    *
from
    zipcode_distances z 
inner join
    venues v    
    on z.zipcode_to=v.zipcode
inner join
    events e
    on v.id=e.venue_id
where
    z.z         


        

Answer 1

You could use a subquery:

select * from zipcode_distances z, venues v, events e
where
    z.id in (select id from zipcode z where z.zipcode_from='92108' and z.distance <= 5)
    and z.zipcode_to=v.zipcode
    and v.id=e.venue_id