> =# \d n_traffic > Table "public.n_traffic" > Column | Type | Modifiers > --------------+-----------------------------+------------------------------ > login_id | integer | not null > traftype_id | integer | not null > collect_time | timestamp without time zone | not null default now() > bytes_in | bigint | not null default (0)::bigint > bytes_out | bigint | not null default (0)::bigint > Indexes: > "n_traffic_collect_time" btree (collect_time) > "n_traffic_login_id" btree (login_id) > "n_traffic_login_id_collect_time" btree (login_id, collect_time) > Foreign-key constraints: > "n_traffic_login_id_fkey" FOREIGN KEY (login_id) REFERENCES > n_logins(login_id) ON UPDATE CASCADE > "n_traffic_traftype_id_fkey" FOREIGN KEY (traftype_id) REFERENCES > n_traftypes(traftype_id) ON UPDATE CASCADE Why do you have indexes on both LOGIN_ID *and* LOGIN_ID + COLLECT_TIME?
It is because I think that queries which use only LOGIN_ID field will use (faster) LOGIN_IDonly index... For me, speed of insertions is not a primary task here (robot is not confused by delays...), but select is. So I keep both indexes.
ISTM that you can drop the LOGIN_ID index.
-- engineer
