How to take 5 continuously absent days in SQL

/*
Drop table Attendence

Create table Attendence(attid	int,
CourseId	int,
CourseCatID	int,
RegNo	nvarchar(7),
Attdate	date,
Attendance	char(1),
createUser	int,
createdDate	date,
updatedUser	int,
updatedDate	date,
statuse	int)




Insert into Attendence(attid,CourseId,CourseCatID,RegNo,Attdate,Attendance,createUser,createdDate,updatedUser,updatedDate,statuse) values (1	,1	,1	,'FS001',	'2017-07-18',	'A',	1,	'2017-07-18',	1,	'2017-07-18',	1)
Insert into Attendence(attid,CourseId,CourseCatID,RegNo,Attdate,Attendance,createUser,createdDate,updatedUser,updatedDate,statuse) values (2	,1	,1	,'FS002',	'2017-07-18',	'P',	1,	'2017-07-18',	1,	'2017-07-18',	1)
Insert into Attendence(attid,CourseId,CourseCatID,RegNo,Attdate,Attendance,createUser,createdDate,updatedUser,updatedDate,statuse) values (3	,1	,1	,'FS002',	'2017-07-19',	'A',	1,	'2017-07-18',	1,	'2017-07-18',	0)
Insert into Attendence(attid,CourseId,CourseCatID,RegNo,Attdate,Attendance,createUser,createdDate,updatedUser,updatedDate,statuse) values (4	,1	,1	,'FS002',	'2017-08-01',	'A',	1,	'2017-08-01',	1,	'2017-08-01',	1)
Insert into Attendence(attid,CourseId,CourseCatID,RegNo,Attdate,Attendance,createUser,createdDate,updatedUser,updatedDate,statuse) values (5	,1	,1	,'FS002',	'2017-08-02',	'A',	1,	'2017-08-02',	1,	'2017-08-01',	1)
Insert into Attendence(attid,CourseId,CourseCatID,RegNo,Attdate,Attendance,createUser,createdDate,updatedUser,updatedDate,statuse) values (6	,1	,1	,'FS002',	'2017-08-03',	'A',	1,	'2017-08-03',	1,	'2017-08-01',	1)
Insert into Attendence(attid,CourseId,CourseCatID,RegNo,Attdate,Attendance,createUser,createdDate,updatedUser,updatedDate,statuse) values (7	,1	,1	,'FS002',	'2017-08-04',	'A',	1,	'2017-08-04',	1,	'2017-08-01',	1)
Insert into Attendence(attid,CourseId,CourseCatID,RegNo,Attdate,Attendance,createUser,createdDate,updatedUser,updatedDate,statuse) values (8	,1	,1	,'FS002',	'2017-08-05',	'p',	1,	'2017-08-05',	1,	'2017-08-01',	1)
Insert into Attendence(attid,CourseId,CourseCatID,RegNo,Attdate,Attendance,createUser,createdDate,updatedUser,updatedDate,statuse) values (9	,1	,1	,'FS002',	'2017-08-06',	'p',	1,	'2017-08-05',	1,	'2017-08-01',	1)
Insert into Attendence(attid,CourseId,CourseCatID,RegNo,Attdate,Attendance,createUser,createdDate,updatedUser,updatedDate,statuse) values (10	,1	,1	,'FS002',	'2017-08-07',	'p',	1,	'2017-08-05',	1,	'2017-08-01',	1)
Insert into Attendence(attid,CourseId,CourseCatID,RegNo,Attdate,Attendance,createUser,createdDate,updatedUser,updatedDate,statuse) values (11	,1	,1	,'FS002',	'2017-08-08',	'A',	1,	'2017-08-05',	1,	'2017-08-01',	0)

*/


Declare @LeaveAttendence as table(Id int identity(1,1), RegNo nvarchar(7), LeaveStartDate Date, LeaveEndDate Date, ContinuousLeave int)




Declare @incrementCount int
Declare @totalCount int


Select @totalCount = Count(*) from Attendence
Select @incrementCount = Min(attid) from Attendence

Declare @RegNo nvarchar(7), @LeaveStartDate Date, @LeaveEndDate Date, @Attendance char(1)

while @incrementCount < @totalCount
Begin

Select @RegNo = RegNo, @LeaveStartDate = Attdate, @LeaveEndDate = Attdate, @Attendance = Attendance from Attendence where attid = @incrementCount

If Not Exists(Select 1 from @LeaveAttendence where @RegNo = RegNo AND ContinuousLeave < 5)
Begin
	Insert into @LeaveAttendence(RegNo,LeaveStartDate,LeaveEndDate,ContinuousLeave) values (@RegNo,null,null,0)
End


if @Attendance = 'A' 
Begin

  print Cast(@RegNo as varchar) + ' - ' + Cast(@LeaveEndDate as varchar) 

	If Exists(Select 1 from @LeaveAttendence where @RegNo = RegNo AND ContinuousLeave > 0)
	Begin
		Update @LeaveAttendence set LeaveEndDate = @LeaveEndDate,ContinuousLeave = ContinuousLeave + 1 where @RegNo = RegNo and ContinuousLeave < 5
	End
	Else
	Begin
		Update @LeaveAttendence set LeaveStartDate = @LeaveStartDate, LeaveEndDate = @LeaveEndDate,ContinuousLeave = 1 where @RegNo = RegNo and ContinuousLeave < 5
	End
End
Else
Begin
	Update @LeaveAttendence set LeaveStartDate = null, LeaveEndDate = null,ContinuousLeave = 0 where @RegNo = RegNo and ContinuousLeave < 5
End

SET @incrementCount = @incrementCount + 1
END

Select * from @LeaveAttendence where ContinuousLeave > 4

create table courseattend
(
regno            varchar2(5) not null,
attdate          date not null,
attendance       char(1) not null
)
;

select regno, fromdate, tilldate
from
(
select regno, attdate fromdate, 
max(attdate) over 
	(partition by regno order by attdate rows between current row and 4 following) tilldate,
sum(case attendance when 'A' then 1 else 0 end) over 
	(partition by regno order by attdate rows between current row and 4 following) absentcount,
sum(1) over 
	(partition by regno order by attdate rows between current row and 4 following) numrecs
from courseattend
)
where absentcount = 5
order by 1, 2;