Cursor in SQL Server :–
- A cursor is a pointer to resultset which contains set of records return by the select statement.
- Using the cursor we can process the record in resultset.
- cursor are used to process the multiple records.
- Cursor will reduce no. of trips to database server.
To use cursor follow below steps :-
- Declare cursor
- Open cursor
- Fetch records from cursor
- Close cursor
- Deallocate cursor.
(I) Declare the cursor in SQL Server examples :-
Syntax :- Declare<name> cursor[options] for select statement.
Example :- Declare c1 cursor for select * from emp.
When cursor is declared ,so context area is created in client side.
(II) Open cursor in SQL Server examples :-
Syntax :- Open<cursor name>
Example :- open c1
when cursor is opened
- (A) The select statement is submitted to database server.
- (B) The records return by the select statement are loaded in context area.
- (C) cursor will be pointing to the that context area.
(III) Fetch records from cursor in SQL Server examples :-
The fetch statement is used to fetch record from the context area and load the record into variables.
Syntax :- Fetch next/prior/first/last/absolute n/relative n from<cursor> into <variables>
Example :- fetch next from c1 into @eno @ename @sal
Fitch statement fitches only are record but process multiple records fetch statement should placed inside the loop.
(IV) Close Cursor in SQL Server examples :-
Syntax : close <cursor>
Example : close c1.
(V) Deallocate cursor in SQL Server examples :-
Syntax : deallocate <cursor name>
Example :- deallocate c1
The memory allocates for the cursor is released.