specific status on consecutive days

Question

I have a MySQL table ATT which has EMP_ID , ATT_DATE , ATT_STATUS with ATT_STATUS with different values 1-Present,2-Absent,3-Weekly-off. I want to find out those EMP_ID 's which have status 2 consecutively for 10 days in a given date range.

Please help

Answer 1

Please have a try with this:

SELECT EMP_ID FROM (
SELECT
IF((@prevDate!=(q.ATT_DATE - INTERVAL 1 DAY)) OR (@prevEmp!=q.EMP_ID) OR (q.ATT_STATUS != 2), @rownum:=@rownum+1, @rownum:=@rownum) AS rownumber, @prevDate:=q.ATT_DATE, @prevEmp:=q.EMP_ID, q.*
FROM (
SELECT
EMP_ID
, ATT_DATE
, ATT_STATUS
FROM
org_tb_dailyattendance, (SELECT @rownum:=0, @prevDate:='', @prevEmp:=0) vars
WHERE ATT_DATE BETWEEN '2013-01-01' AND '2013-02-15'
ORDER BY EMP_ID, ATT_DATE, ATT_STATUS
) q
) sq
GROUP BY EMP_ID, rownumber
HAVING COUNT(*) >= 10

The logic is, to first sort the table by employee id and the dates. Then introduce a rownumber which increases only if

• the days are not consecutive or
• the employee id is not the previous one or
• the status is not 2

Then I just grouped by this rownumber and counted if there are 10 rows in each group. That should be the ones who were absent for 10 days or more.

Answer 2

Have you tried something like this

SELECT EMP_ID count(*) as consecutive_count min(ATT_DATE)
FROM (SELECT * FROM ATT ORDER BY EMP_ID) 
GROUP BY EMP_ID, ATT_DATE
WHERE ATT_STATUS = 2
HAVING consecutive_count > 10