SELECT COUNT( a.id )
FROM table_1 a
LEFT JOIN table_2 b ON a.id = b.id
LEFT JOIN table_3 y ON a.foo= y.id
WHERE a.bar =1
AND a.field =3
AND b.mydate <= 1159438132
AND b.status =2
AND (
y.myfield IS NULL
OR y.myfield !=2
)
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE b ref status,mydate,id,mydate_2 status 1 const 10301 Using where
1 SIMPLE a eq_ref PRIMARY,bar,field PRIMARY 4 database_com.b.id 1 Using where
1 SIMPLE y eq_ref PRIMARY PRIMARY 4 database_com.a.foo 1 Using where