Question

I have a table with 900k+ records

it takes a minute or more to run this query:

SELECT
  t.user_id,
  SUM(t.direction = "i") AS 'num_in',
  SUM(t.direction = "o") AS 'num_out'
FROM tbl_user_reports t
WHERE t.bound_time BETWEEN '2011-02-01' AND '2011-02-28'
GROUP BY t.user_id
HAVING t.user_id IS NOT NULL
ORDER BY num_in DESC
LIMIT 10;

can you tell me how to query the result faster?

— more info —
structure:

id int(11) unsigned NOT NULL
subscriber varchar(255) NULL
user_id int(11) unsigned NULL
carrier_id int(11) unsigned NOT NULL
pool_id int(11) unsigned NOT NULL
service_id int(11) unsigned NOT NULL
persona_id int(11) unsigned NULL
inbound_id int(11) unsigned NULL
outbound_id int(11) unsigned NULL
bound_time datetime NOT NULL
direction varchar(1) NOT NULL

indexes:

bound_timebound_time
FK_tbl_user_reportspersona_id
FK_tbl_user_reports_messageinbound_id
FK_tbl_user_reports_serviceservice_id
FK_tbl_user_reports_poolpool_id
FK_tbl_user_reports_useruser_id
FK_tbl_user_reports_carriercarrier_id
FK_tbl_user_reports_subscribersubscriber
FK_tbl_user_reports_outboundoutbound_id
directiondirection

Answer 1

You may want to try a compound index on

(bound_time, user_id, direction)

Contains all the fields you need and can be narrowed by the date range very efficiently.