This document discusses stored procedures in SQL Server. It begins by explaining that stored procedures allow encapsulation of repetitive tasks and are stored in the database data dictionary. It then shows how stored procedures reduce network traffic and client-server communication compared to individual SQL statements. The document provides examples of how to create a stored procedure using CREATE PROCEDURE and how to call it using EXEC. It notes advantages like precompiled execution, reduced traffic, code reuse, and security control. It also demonstrates using parameters, loops, conditions and variables inside stored procedures.
2. Stored Procedures
• A stored procedure is a method to encapsulate
repetitive tasks.
• A stored Procedure is actually stored in
database data dictionary
3. Without Stored Procedure
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5. Advantages
• Precompiled Execution
•sqlserver compiles each stored procedure once and
then re utilizes the execution plan. This result in
tremendous performance boosts when stored
procedures are called repeatedly
• Reduced client server traffic
•If network traffic is concerned you will be happy to
learn that stored procedures can reduce long sql
queries to a single line that is transmitted between
application program and database server.
6. Advantages
• Efficient reuse of code and programming abstraction
•Stored procedures can be used by multiple programs
and users. If you utilize them in a planned manner,
you’ll find the development cycle takes less time.
• Enhanced Security Control
•You can grant users permission to execute stored
procedure independently of underlying table
permissions
7. How to create Stored Procedure ?
example
CREATE PROCEDURE getName(@id int)
as
BEGIN
Select * from tbl_user where userid=@id;
END
EXEC getName @id=1 ;
8. How to create Stored Procedure ?
example
CREATE PROCEDURE getName(@id int)
BEGIN
Select * from tbl_user where userid=@id;
END
EXEC getName @id=1;
Is the keyword to create a new stored
procedure .we can use proc also
9. How to create Stored Procedure ?
example
CREATE PROCEDURE getName(@id int)
BEGIN
Select * from tbl_user where userid=@id;
END
EXEC getName @id=1
Is the name of the stored
procedure that we are creating
10. How to create Stored Procedure
? example
CREATE PROCEDURE getName ( @id int)
BEGIN
Select * from tbl_user where userid=@id;
END
Call getName @id=1;
Is the body of the stored procedure. Here we
have only a single select query statements.
We can also apply logic using the below
• DECLARE a INT; : declaring an integer
type variable
• SET a=20; : Setting value of a
to 20
• IF THEN
• ELSE IF
label1: LOOP
SET p1 = p1 + 1;
IF p1 < 10 THEN
ITERATE label1;
END IF;
LEAVE label1;
END LOOP label1;
: For conditions
: Loops
11. How to create Stored Procedure ?
example
CREATE PROCEDURE getName ( @id int)
BEGIN
Select * from tbl_user where userid=@id;
END
exec getName=@id=1;
12. How to create Stored Procedure ?
example
CREATE PROCEDURE getName ( @id int)
BEGIN
Select * from tbl_user where userid=@id;
END
exec getName @id=1;
Calling the stored procedure we’ve
just created and passing the value
1001 as its argument
13. How to create Stored Procedure ?
example
CREATE PROCEDURE getSale1(@id int,@pri int output ,@sal int
output)
as BEGIN
Select @pri=sum(price), @sal=avg(sales) from tbl_sales
where pk_int_id=@id;
END
declare @total int
declare @sale int
exec getSale1 @id=1,@pri=@total output,@sal=@sale output;
select @total; select @sale;
14. • Create the below table
Create a stored procedure called
– csp_getSalary(1000) : should return the salary of employee with id as
passed in the argument
– Csp_getSalaryAtPlace(‘calicut’,@total) : should return the total salary of
employees from a perticular place
Live Task
Tbl_employee
Emp_id Emp_name Emp_age Emp_email int_salary vchr_place
1000 Deepak 24 dk@gmail.com 10000 Calicut
1001 Aneesh 23 an@gmail.com 20000 Cochin
1002 Naveen 25 nn@gmail.com 10000 Calicut
1003 Jacob 25 jb@gmail.com 30000 Cochin
15. Cursors
• SELECT INTO is fine for single-row queries, but many
applications require the querying of multiple rows of data.
You will use a cursor in SQL Server to accomplish this.
• A cursor lets you fetch one or more rows from a SQL result set
into stored program variables, usually with the intention of
performing some row-by-row processing on the result set.
16. Cursors - example
create procedure CSP_status_change
as begin
declare @done int;
set @done=0;
declare @studId int;
declare @studStatus bit;
declare @dateDif int;
declare @myCur cursor
set @myCur = cursor for select
pk_int_student_id,bln_student_status,
datediff(day,dat_fph_date,GETDATE())as date_difference from
tbl_students
join tbl_fee_payment_history on
fk_int_student_id=pk_int_student_id;
open @myCur
17. fetch next from @myCur into @studId,@studStatus,@dateDif;
while @@FETCH_STATUS = 0 begin
if @dateDif>15
update tbl_students set bln_student_status=0 where
pk_int_student_id=@studId;
else
update tbl_students set bln_student_status=1 where
pk_int_student_id=@studId;
fetch next from @myCur into @studId,@studStatus,@dateDif;
end;
close @myCur;
deallocate @myCur;
END;
exec CSP_status_change;
fetch next from @myCur
20. • Why should someone use stored procedure?
– To avoid data redundancy
– To reduce network traffic between
application server and database server
– To ensure data integrity
Self Check !!
21. • Why should someone use stored procedure?
– To avoid data redundancy
– To reduce network traffic between
application server and database server
– To ensure data integrity
Self Check !!
22. Self Check !!
• Why should someone change the delimiter before
creating a stored procedure?
– To use ; as separation between multiple statements in a
stored procedure body
– To push the server to compile the whole body of stored
procedure all together
– Both of above
– None of above
23. Self Check !!
• Why should someone change the delimiter before
creating a stored procedure?
– To use ; as separation between multiple statements in a
stored procedure body
– To push the server to compile the whole body of stored
procedure all together
– Both of above
– None of above
24. Self Check !!
CREATE PROCEDURE simpleProc ( OUT param1 INT)
BEGIN
SELECT COUNT(*) INTO param1 FROM t ;
END
EXEC simpleProc(@a);
Select @a ;
25. Self Check !!
CREATE PROCEDURE simpleProc ( @param1 INT)
BEGIN
SELECT COUNT(*) INTO param1 FROM t ;
END
exec simpleProc(@a);
Select @a ;
26. Self Check !!
What are the uses of cursors?
•For extracting multiple rows from a table
•For extracting multiple rows into variables from a table
•For setting handlers
27. Self Check !!
What are the uses of cursors?
•For extracting multiple rows from a table
•For extracting multiple rows into variables from a table
•For setting handlers