What is the MySQL SQL optimization method?
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A sql was found in slowlog for more than 10 seconds.
# Time: 2017-03-02T18:41:50.201376+08:00
# User@Host: oms_ readonly[ oms _ readonly] @ [10.xx.xx.xx] Id: 54124620
# Query_time: 11.005894 Lock_time: 0.000223 Rows_sent: 20 Rows_examined: 1838114
SET timestamp=1488451310
Select * from customers where `type` = 1 AND `status`
< 7 AND `isarea` = 6 AND `into_time`>= '2016-12-01'AND `into_ time` explain select * from customers where `type` = 1 AND `status`
< 7 AND `isarea` = 6 AND `into_time`>= '2016-12-01'AND `into_ time` select count (*) from customers where `type` = 1
+-+
| | count (*) |
+-+
| | 2373175 |
+-+
1 row in set (1.53 sec)
Mysql > select count (*) from customers where `status`
< 7; ->+-+
| | count (*) |
+-+
| | 2494232 |
+-+
1 row in set (3.16 sec)
Mysql > select count (*) from customers where `isarea` = 6
+-+
| | count (*) |
+-+
| | 135347 |
+-+
1 row in set (0.15 sec)
Mysql > select count (*) from customers where `into_ time` > = '2016-12-01'AND `into_ time` explain select * from customers use index (isarea) where `type` = 1 AND `status`
< 7 AND `isarea` = 6 AND `into_time`>= '2016-12-01'AND `into_ time`
