How can i rewrite this query for faster execution - mysql

Question

SELECT s1.ID FROM binventory_ostemp s1 JOIN
( SELECT Cust_FkId, ProcessID, MAX(Service_Duration) AS duration
FROM binventory_ostemp WHERE ProcessID='4d2d6068678bc' AND Overall_Rank IN
(
SELECT MIN(Overall_Rank) FROM binventory_ostemp WHERE ProcessID='4d2d6068678bc' GROUP BY Cust_FkId
)
GROUP BY Cust_FkId
) AS s2 ON s1.Cust_FkId = s2.Cust_FkId AND s1.ProcessID=s2.ProcessID
AND s1.Service_Duration=s2.duration AND s1.ProcessID='4d2d6068678bc'
GROUP BY s1.Cust_FkId
It just goes away if there are more than 10K rows in that table. What it does is find rows for each customer who has min. of overall rank and in those max. of service duration for a given processid
Table Data
ID Cust_FkId Overall_Rank Service_Duration ProcessID
1 23 2 30 4d2d6068678bc
2 23 1 45 4d2d6068678bc
3 23 1 60 4d2d6068678bc
4 56 3 90 4d2d6068678bc
5 56 2 50 4d2d6068678bc
6 56 2 85 4d2d6068678bc
Result Data
Result ID values must be 3 and 6 only

Answer 1

Following select might be faster.
(Covering) Indexes on
Cust_FkID, Overall_Rank
Cust_FkID, Service_Duration
Cust_FkID, Overall_Rank, Service_Duration
Overall_Rank
Service_Duration
Remove the indexes that don't get used by looking at the execution plan.
SQL Statement
SELECT b.*
FROM binventory_ostemp b
INNER JOIN (
SELECT b.Cust_FkID
, ovr.Overall_Rank
, MAX(Service_Duration) AS Service_Duration
FROM binventory_ostemp b
INNER JOIN (
SELECT Cust_FkID
, MIN(Overall_Rank) AS Overall_Rank
FROM binventory_ostemp
GROUP BY
Cust_FkID
) ovr ON ovr.Cust_FkID = b.Cust_FKID
AND ovr.Overall_Rank = b.Overall_Rank
GROUP BY
b.Cust_FkID
, ovr.Overall_Rank
) ovrs ON ovrs.Cust_FkID = b.Cust_FkID
AND ovrs.Overall_Rank = b.Overall_Rank
AND ovrs.Service_Duration = b.Service_Duration