Cursor In SQL SERVER

Cursor:- Cursor is  a database object to retrieve data from a result set one row at time. we use cursor when we need to update record databse table in Sigleton fashion means row wise.



  For Exampl :
   select * from Products

 know i want change  unit price of unit of each based on some condition.

Declare @UnitPrice decimal(5,2)
Declare @ProductId int
Declare UnitPriceUpdateCursore  Cursor FOR
Select ProductID From Products
open  UnitPriceUpdateCursore
Fetch Next From UnitPriceUpdateCursore into @ProductId
While (@@Fetch_Status=0)
Begin
select @UnitPrice=UnitPrice from Products

Begin Update Products set UnitPrice = case when UnitPrice between 5 And 10 then 15
                     when UnitPrice  between 11 AND 15  then 20
     else UnitPrice
                    end
Where ProductID=@ProductId
Fetch Next From UnitPriceUpdateCursore into @ProductId
END
End
Close UnitPriceUpdateCursore
Deallocate UnitPriceUpdateCursore
Set NoCount Off