SELECT

Studentid,

MIN(dateid) AS First_Absence_Date,

MAX(dateid) AS Last_Absence_Date,

COUNT(*) AS Total_Consecutive_Absences

FROM (

SELECT

Studentid, attendanceind, dateid,

ROW_NUMBER() OVER (PARTITION BY Studentid ORDER BY dateid) -

ROW_NUMBER() OVER (PARTITION BY Studentid, attendanceind ORDER BY dateid) AS Grp#

FROM #x x --<<-- change to your table name

) AS derived

WHERE

attendanceind = 0

GROUP BY

Studentid, grp#

HAVING

COUNT(*) >= 15

ORDER BY

Studentid, First_Absence_Date