如何从MySQL中的单个表中获取不同的计数

Question

I have a table named - studentId_t which is having fields:

• SrNo.
• classId
• StudentId
• StudentName
• Status
• Creation Date
• Modified Date

and another table named studentE which is having fields

• SrNo.
• classId
• studentId
• studentAdd
• EId

-- I want to check status of student and I am having only E_id

I was trying query like ..

SELECT COUNT(1) AS ST FROM `StuInfo`.`studentId_t` S, `StuInfo`.`studentE` SE
    WHERE S.`status` = 'ST'
    AND SE.`studentId` = S.`studentId`
    AND SE.`EId` = 1

but here, I want to calculate status in (ST, BS, BH, GN), So how can i calculate it in single query from above query I am able to calculate single status, I want multiple status

Answer 1

USE SUM() with if,else conditions oriented to all status.

Try like below:

SELECT SUM(if(status='ST',1,0))  AS ST , SUM(if(status='BS',1,0))  AS   BS,
SUM(if(status='BH',1,0))  AS BH,SUM(if(status='GN',1,0))  AS GN
FROM StuInfo.studentId_t S, StuInfo.studentE SE
WHERE S.status IN ('ST', 'BH','BS','GN') AND SE.studentId = S.studentId AND SE.EId = 1