Microsoft SQL Server Tutorials

SQL - Forward only and Scroll Cursors

Forward only and Scroll Cursors in SQL Server

If a cursor is declare as forward only it allows you to navigate only to the next records in sequential order and more over it supports only a singleton fashion method that is fetch next(one-by-one) where as a scroll cursor allows you to navigate/fetch Bidirectionally that is top- bottam or bottom-top also.And it supports six different fetch methods are

Fetch Next,Fetch First,Fetch Last,Fetch Prior,Fetch Absolute ,Fetch Relative.

 

Example: 

Create an explicit cursor to fetch the records One-by-One manner(First-Last) from the table.

declare c1 cursor for select * from dept

open c1

fetch next from c1

while @@FETCH_STATUS=0 begin

fetch next from c1

end close c1

deallocate c1

 

Create an explicit cursor to fetch the records from bottom -first (Last- First)from the table.

 

Sol: declare c1 cursor scroll for select from dept

open c1

fetch last from c1

while @@FETCH_STATUS=0 begin

fetch prior from c1

end close c1

deallocate c1
 

Create an explicit cursor on fetching methods.

 

declare @id int declare cursor scroll

for select sid from student

open e

fetch next from into @id

print @id

fetch last from into @id

print @id

fetch prior from into @id

print @id

fetch absolute from into @id

print @id

fetch relative -1 from into @id

print @id

fetch first from into @id

print @id close deallocate e

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Microsoft SQL Server

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Forward only and Scroll Cursors in SQL Server

If a cursor is declare as forward only it allows you to navigate only to the next records in sequential order and more over it supports only a singleton fashion method that is fetch next(one-by-one) where as a scroll cursor allows you to navigate/fetch Bidirectionally that is top- bottam or bottom-top also.And it supports six different fetch methods are

Fetch Next,Fetch First,Fetch Last,Fetch Prior,Fetch Absolute ,Fetch Relative.

 

Example: 

Create an explicit cursor to fetch the records One-by-One manner(First-Last) from the table.

declare c1 cursor for select * from dept

open c1

fetch next from c1

while @@FETCH_STATUS=0 begin

fetch next from c1

end close c1

deallocate c1

 

Create an explicit cursor to fetch the records from bottom -first (Last- First)from the table.

 

Sol: declare c1 cursor scroll for select from dept

open c1

fetch last from c1

while @@FETCH_STATUS=0 begin

fetch prior from c1

end close c1

deallocate c1
 

Create an explicit cursor on fetching methods.

 

declare @id int declare cursor scroll

for select sid from student

open e

fetch next from into @id

print @id

fetch last from into @id

print @id

fetch prior from into @id

print @id

fetch absolute from into @id

print @id

fetch relative -1 from into @id

print @id

fetch first from into @id

print @id close deallocate e

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