複合索引順序MySQL查詢

我想優化下面的mysql查詢。它運行約2.5秒。我已經閱讀了複合索引，但我希望有人能夠幫助我理解你如何將複合索引與這些包含多個聯接的查詢複合，其中許多條件（包括日期範圍），一個組合以及一個order by一個計算值。我是否缺少有用的複合索引？有沒有更有效的方法，我應該從這些表中提取數據？任何幫助非常感謝！複合索引順序MySQL查詢

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

這裏是EXPLAIN輸出：

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

來源

2017-06-23 b.digg

周圍不知道你的數據進行任何刪除無用的（），您的查詢暗示索引'辦公室（刪除，可見，branch_id）'。然而，這張表似乎只包含少數幾行，因此這個索引可能沒有多大幫助;要選擇更好的策略，您可以嘗試識別強大的過濾器。如果例如99％的數據將具有'customer.saved = 1'或'appointment.current！= 1'，您可以嘗試使用它來優化您的查詢 - 但這取決於您的數據。另外，爲了清楚起見，你應該用'join'來替換除最後一個'left join'（如果'office.branch_id'爲'not null'，那麼最後一個也是如此） – Solarflare

一個建議

條件

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

來源

2017-06-23 05:19:52 scaisEdge

複合索引順序MySQL查詢

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