Question

我正在尝试优化以下mysql查询。它运行大约2.5秒。我已经阅读了复合索引，但我希望有人可以帮助我理解你如何使用包含多个连接的查询来复合索引，许多条件（包括日期范围），分组依据和顺序计算值。我错过了有用的复合指数吗？我是否应该从这些表中提取数据的更有效方法？非常感谢任何帮助！

SELECT 
branch.name AS branch,
SUM(appointment.status =  'completed') AS `Completed`, 
SUM(appointment.status =  'cancelled') AS `Cancelled`, 
SUM(appointment.status =  'not completed') AS `Not Completed`, 
SUM(appointment.status != 'rescheduled') AS `Total`
FROM rep
JOIN customer ON rep.id = customer.rep_id
JOIN office ON rep.office_id = office.id
JOIN appointment ON customer.id = appointment.customer_id
JOIN branch ON office.branch_id = branch.id
WHERE rep.active= 1 
AND rep.group IN (1,2,3) 
AND rep.deleted = 0 
AND customer.saved = 0 
AND (customer.rep_id != appointment.closed_by OR appointment.closed_by IS NULL)
AND customer.rep_id != 0 
AND customer.deleted = 0
AND office.visible = 1 
AND office.deleted = 0 
AND appointment.date >= '2016-12-01'
AND appointment.date < '2017-11-30' 
AND appointment.current = 1 
GROUP BY branch.id
ORDER BY Completed

这是EXPLAIN输出：

id: 1
select_type: simple
table: office
type: ref
possible_keys: PRIMARY, deleted_branchID_name, deleted_visible 
key: deleted_visible
key_len: 5
ref: const,const
rows:  73
Extra: Using index condition; Using temporary; Using filesort

id: 1
select_type: simple
table: branch
type: eq_ref
possible_keys: PRIMARY
key: PRIMARY
key_len: 4
ref: office.branch_id
rows: 1
Extra: NULL

id: 1
select_type:  simple
table: rep
type: ref
possible_keys: PRIMARY, group_id, office_id, active_deleted
key: office_id
key_len: 5
ref: office.id
rows:  57 
Extra: Using index condition; Using where

id:  1
select_type:  simple
table:  customer
type: ref
possible_keys: PRIMARY, rep_id
key: rep_id
key_len: 4
ref: rep.id
rows:  61 
Extra: Using where

id: 1
select_type: simple
table: appointment
type: ref
possible_keys: date, customer_id, closedByID_date, isCurrent_date
key: customer_id
key_len: 4
ref: customer.id
rows: 1
Extra: Using where

Answer 1

建议

在条件

周围删除unuseful（）

  LEFT JOIN customer ON rep.id = customer.rep_id
  LEFT JOIN office ON rep.office_id = office.id
  LEFT JOIN appointment ON customer.id = appointment.customer_id
  LEFT JOIN branch ON office.branch_id = branch.id

复合索引命令MySQL查询

1 个答案: