1. STORED PROCEDURE

2. STORED PROCEDURE
RAJISHMA T.
19/04/89

3. • A Stored procedure is a procedure that is stored in
a database.
• It has a name,parameter list and sql statements.
• The first part of the SQL statement that creates a
stored procedure is the words "CREATE
PROCEDURE".
• CREATE PROCEDURE p1 () SELECT * FROM t; /
• The second part is the procedure name. The name
of this new procedure will be p1
• My sql statements are legal in the body of a stored
procedure.

4. • We cant put database manipulation statements that
manipulate a routine such as create
procedure,create function,drop function,drop
procedure,alter procedure etc etc.
• Statements like use database are also illegal.
• Call the procedure
 To call a procedure we use the call
keyword and then the procedure name
and paranthesis.
Eg:call p1();

5. ADVANTAGES:
• Stored procedure increases performance of
application.
• Stored procedure reduced the traffic between
application and database server.
• Stored procedure is reusable and transparent
to any application which wants to use it.
• Stored procedure is secured.

6. CHARACTERESTIC CLAUSES
• There is some clauses which describes the characterestics
of the procedure.
• Consider the eg below with charactarestics clauses.
• Create procedure p2()
language SQL
not deterministic
SQL security defines
comment ‘a procedure’
select * from t

7. VARIABLES
 the statements used to define variables in a compount
statement is declare.
 Eg: declare a int;
 Variables are declared between the begin and end tag.
 Scope of the variable:
CREATE PROCEDURE p()
BEGIN
DECLARE x1 CHAR(5) DEFAULT 'outer';
BEGIN
DECLARE x1 CHAR(5) DEFAULT 'inner';
SELECT x1;
END;
SELECT x1;
END;

8. Call scope example: call p()
X1
inner
x1
outer

9. PARAMETERS
• 1. CREATE PROCEDURE p() ...
• 2. CREATE PROCEDURE p([IN] name data-type)
...
• 3. CREATE PROCEDURE p(OUT name data-
type) ...
• 4. CREATE PROCEDURE p(INOUT name data-
type)

10. IN EG:
Delimiter //
create procedure p1(in p int)
Begin
declare x int;
Set x = p ;
Select x;
End //
Call p(123);

11. OUT EG:
CREATE PROCEDURE p2 (OUT p INT)
Begin
SET p = -5;
select p;
End //
Call p2(@o)

12. INOUT EG:
CREATE PROCEDURE P3(INOUT P INT)
BEGIN
SET P=P*2;
Select p;
END //
Set @y=5;
Call p3(@y);

13. IF-THEN -ELSE
CREATE PROCEDURE p3(IN parameter1 INT)
BEGIN
DECLARE variable1 INT;
SET variable1 = parameter1 + 1;
IF variable1 = 0 THEN
INSERT INTO t VALUES (17);
END IF;
IF parameter1 = 0 THEN
INSERT INTO T VALUES(15);
ELSE
INSERT INTO T VALUES(15);
END IF;
END; //

14. CASE:
CREATE PROCEDURE p4(IN parameter1 INT)
BEGIN
DECLARE variable1 INT;
SET variable1 = parameter1 + 1;
CASE variable1
WHEN 0 THEN INSERT INTO t VALUES (17);
WHEN 1 THEN INSERT INTO t VALUES (18);
ELSE INSERT INTO t VALUES (19);
END CASE;
END; //

15. WHILE------END WHILE
CREATE PROCEDURE p5 ()
BEGIN
DECLARE v INT;
SET v = 0;
WHILE v < 5 DO
INSERT INTO t VALUES (v);
SET v = v + 1;
END WHILE;
END; //

16. REPEAT------END REPEAT
CREATE PROCEDURE p6 ()
BEGIN
DECLARE v INT;
SET v = 0;
REPEAT
INSERT INTO t VALUES (v);
SET v = v + 1;
UNTIL v >= 5
END REPEAT;
END; //

17. LOOP-------END LOOP
CREATE PROCEDURE p7 ()
BEGIN
DECLARE v INT;
SET v = 0;
loop_label: LOOP
INSERT INTO t VALUES (v);
SET v = v + 1;
IF v >= 5 THEN
LEAVE loop_label;
END IF;
END LOOP;
• END; //

18. GO TO:
CREATE PROCEDURE p...
BEGIN
...............
LABEL label_name;
...............
GOTO label_name;
...............
END

19. ERROR HANDLNG
• SYNTAX:
DECLARE
{ EXIT | CONTINUE }
HANDLER FOR
{ error-number | { SQLSTATE error-string } | condition }
SQL statement

20. EXIT HANDLER EG:
Create procedure department_ex(in dept_name varchar(30),in
dept_location varchar(30),in id int)
Begin
declare d_key int default 0;
Begin
declare exit handler for 1062 set d_key=1;
insert into departments
values(dept_name,dept_location,id);
select concat (‘department’,dept_name,’created successfully’) as
“result”;
end;
If d_key=1 then
select concat(‘failed to insert’,dept_name,’:duplicate key’) as
“result”;
End if
End //

21. CONTINUE HANDLER EG:
Create procedure department_co(in dept_name varchar(30),in dept_location varchar(30),in
id int)
Begin
declare d_key int default 0;
declare exit handler for 1062
begin
set d_key=1;
End;
insert into departments
values(dept_name,dept_location,id);
If d_key=1 then
select concat(‘failed to insert’,dept_name,’:duplicate key’) as
“result”;
else
select concat (‘department’dept_name,’created successfully’) as
“result”;
End if
End //

22. CONDITION:
Declare no_such_table condition for sqlstate
42S02
Declare continue handler for no_such_table
Begin
------body of handler-------
End //

23. CURSORS:
• In sql procedure a cursor make it possible to define a result
set (a set of data rows) and perform complex logic on a row by
row basis.
• To use cursors in SQL procedures, need to do the following:
1:Declare a cursor that defines a result.
2:Open the cursor to establish the result set.
3:Fetch the data into local variables as needed
from the cursor, one row at a time.
4:Close the cursor when done

24. To work with cursors you must use the following
SQL statements:
• DECLARE cursor-name CURSOR FOR SELECT ...;
• OPEN cursor-name;
• FETCH cursor-name INTO variable [, variable];
• CLOSE cursor-name;

25. CURSOR EG:
CREATE PROCEDURE p()
BEGIN
DECLARE id INT;
DECLARE cur_1 CURSOR FOR SELECT i FROM
departments;
OPEN cur_1;
FETCH cur_1 INTO id;
set id=id*2
select id;
CLOSE cur_1;
END;//

26. Thank you