When there is a join, there might be fields with same name, like t1.a = t2.a. We cannot use field name as the key for hashmap in such condition, so we should replace the key by UUID. Checking the field name only when it needs, and operating data via the UUID.
When there is a join, there might be fields with same name, like
t1.a = t2.a. We cannot use field name as the key for hashmap in such condition, so we should replace the key by UUID. Checking the field name only when it needs, and operating data via the UUID.use uuid