Oracle PL/SQL Tutorial/Function Procedure Packages/Procedure
Содержание
- 1 A procedure block.
- 2 Calling a Procedure
- 3 Create or replace a procedure
- 4 Creating stored procedures
- 5 Decrease salary with user procedure
- 6 Demonstration of a nested procedure block
- 7 Execute a procedure
- 8 Forward Referencing
- 9 Insert debug line to the stored procedure with DBMS_OUTPUT.PUT_LINE
- 10 Listing Stored Procedure Information
- 11 Pass ROWTYPE to a procedure
- 12 Procedures
- 13 Storing PL/SQL procedure in the Database
- 14 Wrapping a task into a procedure
A procedure block.
<source lang="sql">
PROCEDURE swapn(num_one IN OUT NUMBER, num_two IN OUT NUMBER) IS
temp_num NUMBER;
BEGIN
temp_num := num_one; num_one := num_two; num_two := temp_num ;
END; /</source>
Calling a Procedure
You call a procedure using the CALL statement.
<source lang="sql">
SQL> SQL> SQL> -- create demo table SQL> create table Employee(
2 ID VARCHAR2(4 BYTE) NOT NULL, 3 First_Name VARCHAR2(10 BYTE), 4 Last_Name VARCHAR2(10 BYTE), 5 Start_Date DATE, 6 End_Date DATE, 7 Salary Number(8,2), 8 City VARCHAR2(10 BYTE), 9 Description VARCHAR2(15 BYTE) 10 ) 11 /
Table created. SQL> SQL> -- prepare data SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values ("01","Jason", "Martin", to_date("19960725","YYYYMMDD"), to_date("20060725","YYYYMMDD"), 1234.56, "Toronto", "Programmer") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("02","Alison", "Mathews", to_date("19760321","YYYYMMDD"), to_date("19860221","YYYYMMDD"), 6661.78, "Vancouver","Tester") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("03","James", "Smith", to_date("19781212","YYYYMMDD"), to_date("19900315","YYYYMMDD"), 6544.78, "Vancouver","Tester") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("04","Celia", "Rice", to_date("19821024","YYYYMMDD"), to_date("19990421","YYYYMMDD"), 2344.78, "Vancouver","Manager") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("05","Robert", "Black", to_date("19840115","YYYYMMDD"), to_date("19980808","YYYYMMDD"), 2334.78, "Vancouver","Tester") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("06","Linda", "Green", to_date("19870730","YYYYMMDD"), to_date("19960104","YYYYMMDD"), 4322.78,"New York", "Tester") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("07","David", "Larry", to_date("19901231","YYYYMMDD"), to_date("19980212","YYYYMMDD"), 7897.78,"New York", "Manager") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("08","James", "Cat", to_date("19960917","YYYYMMDD"), to_date("20020415","YYYYMMDD"), 1232.78,"Vancouver", "Tester") 3 /
1 row created. SQL> SQL> CREATE OR REPLACE PROCEDURE update_employee_salary(
2 p_factor IN NUMBER 3 ) AS 4 v_employee_count INTEGER; 5 BEGIN 6 UPDATE employee 7 SET salary = salary * p_factor; 8 COMMIT; 9 EXCEPTION 10 WHEN OTHERS THEN 11 ROLLBACK; 12 END update_employee_salary; 13 /
Procedure created. SQL> SQL> select * from employee; ID FIRST_NAME LAST_NAME START_DAT END_DATE SALARY CITY DESCRIPTION
---------- ---------- --------- --------- ---------- ---------- ---------------
01 Jason Martin 25-JUL-96 25-JUL-06 1234.56 Toronto Programmer 02 Alison Mathews 21-MAR-76 21-FEB-86 6661.78 Vancouver Tester 03 James Smith 12-DEC-78 15-MAR-90 6544.78 Vancouver Tester 04 Celia Rice 24-OCT-82 21-APR-99 2344.78 Vancouver Manager 05 Robert Black 15-JAN-84 08-AUG-98 2334.78 Vancouver Tester 06 Linda Green 30-JUL-87 04-JAN-96 4322.78 New York Tester 07 David Larry 31-DEC-90 12-FEB-98 7897.78 New York Manager 08 James Cat 17-SEP-96 15-APR-02 1232.78 Vancouver Tester 8 rows selected. SQL> SQL> CALL update_employee_salary(1.5); Call completed. SQL> SQL> select * from employee; ID FIRST_NAME LAST_NAME START_DAT END_DATE SALARY CITY DESCRIPTION
---------- ---------- --------- --------- ---------- ---------- ---------------
01 Jason Martin 25-JUL-96 25-JUL-06 1851.84 Toronto Programmer 02 Alison Mathews 21-MAR-76 21-FEB-86 9992.67 Vancouver Tester 03 James Smith 12-DEC-78 15-MAR-90 9817.17 Vancouver Tester 04 Celia Rice 24-OCT-82 21-APR-99 3517.17 Vancouver Manager 05 Robert Black 15-JAN-84 08-AUG-98 3502.17 Vancouver Tester 06 Linda Green 30-JUL-87 04-JAN-96 6484.17 New York Tester 07 David Larry 31-DEC-90 12-FEB-98 11846.67 New York Manager 08 James Cat 17-SEP-96 15-APR-02 1849.17 Vancouver Tester 8 rows selected. SQL> SQL> SQL> SQL> SQL> -- clean the table SQL> drop table Employee
2 /
Table dropped. SQL></source>
Create or replace a procedure
<source lang="sql">
SQL> create or replace PROCEDURE swapn (num_one IN OUT NUMBER, num_two IN OUT NUMBER) IS
2 temp_num NUMBER; 3 BEGIN 4 temp_num := num_one; 5 num_one := num_two; 6 num_two := temp_num ; 7 END; 8 /
Procedure created. SQL></source>
Creating stored procedures
You can store PL/SQL code inside the database.
You could store the following PL/SQL code as a standalone procedure.
<source lang="sql">
SQL> set SERVEROUTPUT ON SQL> create or replace procedure p_hello
2 is 3 v_string varchar2(256):="Hello, World!"; 4 begin 5 dbms_output.put_line(v_string); 6 end; 7 /
Procedure created.
SQL></source>
Decrease salary with user procedure
<source lang="sql">
SQL> CREATE TABLE EMP(
2 EMPNO NUMBER(4) NOT NULL, 3 ENAME VARCHAR2(10), 4 JOB VARCHAR2(9), 5 MGR NUMBER(4), 6 HIREDATE DATE, 7 SAL NUMBER(7, 2), 8 COMM NUMBER(7, 2), 9 DEPTNO NUMBER(2) 10 );
Table created.
SQL> INSERT INTO EMP VALUES(2, "Jack", "Tester", 6,TO_DATE("20-FEB-1981", "DD-MON-YYYY"), 1600, 300, 30); 1 row created. SQL> INSERT INTO EMP VALUES(3, "Wil", "Tester", 6,TO_DATE("22-FEB-1981", "DD-MON-YYYY"), 1250, 500, 30); 1 row created. SQL> INSERT INTO EMP VALUES(4, "Jane", "Designer", 9,TO_DATE("2-APR-1981", "DD-MON-YYYY"), 2975, NULL, 20); 1 row created. SQL> INSERT INTO EMP VALUES(5, "Mary", "Tester", 6,TO_DATE("28-SEP-1981", "DD-MON-YYYY"), 1250, 1400, 30); 1 row created. SQL> INSERT INTO EMP VALUES(7, "Chris", "Designer", 9,TO_DATE("9-JUN-1981", "DD-MON-YYYY"), 2450, NULL, 10); 1 row created. SQL> INSERT INTO EMP VALUES(8, "Smart", "Helper", 4,TO_DATE("09-DEC-1982", "DD-MON-YYYY"), 3000, NULL, 20); 1 row created. SQL> INSERT INTO EMP VALUES(9, "Peter", "Manager", NULL,TO_DATE("17-NOV-1981", "DD-MON-YYYY"), 5000, NULL, 10); 1 row created. SQL> INSERT INTO EMP VALUES(10, "Take", "Tester", 6,TO_DATE("8-SEP-1981", "DD-MON-YYYY"), 1500, 0, 30); 1 row created.
SQL> SQL> select * from emp; Enter...
2 Jack Tester 6 20-02-1981 1600 300 30 3 Wil Tester 6 22-02-1981 1250 500 30 4 Jane Designer 9 02-04-1981 2975 [N/A] 20 5 Mary Tester 6 28-09-1981 1250 1400 30 7 Chris Designer 9 09-06-1981 2450 [N/A] 10 8 Smart Helper 4 09-12-1982 3000 [N/A] 20 9 Peter Manager [N/A] 17-11-1981 5000 [N/A] 10 10 Take Tester 6 08-09-1981 1500 0 30 13 Fake Helper 4 03-12-1981 3000 [N/A] 20
9 rows selected. SQL> create or replace
2 procedure UPDATE_EMP(p_empno number, p_decrease number) is 3 begin 4 update EMP 5 set SAL = SAL / p_decrease 6 where empno = p_empno; 7 end; 8 /
Procedure created. SQL> exec UPDATE_EMP(1,2); PL/SQL procedure successfully completed. SQL> exec UPDATE_EMP(1,0); PL/SQL procedure successfully completed. SQL> SQL> select * from emp; Enter...
2 Jack Tester 6 20-02-1981 1600 300 30 3 Wil Tester 6 22-02-1981 1250 500 30 4 Jane Designer 9 02-04-1981 2975 [N/A] 20 5 Mary Tester 6 28-09-1981 1250 1400 30 7 Chris Designer 9 09-06-1981 2450 [N/A] 10 8 Smart Helper 4 09-12-1982 3000 [N/A] 20 9 Peter Manager [N/A] 17-11-1981 5000 [N/A] 10 10 Take Tester 6 08-09-1981 1500 0 30 13 Fake Helper 4 03-12-1981 3000 [N/A] 20
9 rows selected. SQL> drop table emp; Table dropped.</source>
Demonstration of a nested procedure block
<source lang="sql">
SQL> SQL> SQL> SET ECHO ON SQL> SET SERVEROUTPUT ON SQL> SQL> DECLARE
2 first_number NUMBER; 3 second_number NUMBER; 4 5 PROCEDURE swapn (num_one IN OUT NUMBER, num_two IN OUT NUMBER) IS 6 temp_num NUMBER; 7 BEGIN 8 temp_num := num_one; 9 num_one := num_two; 10 num_two := temp_num ; 11 END; 12 13 BEGIN 14 15 first_number := 10; 16 second_number := 20; 17 DBMS_OUTPUT.PUT_LINE("First Number = " || TO_CHAR (first_number)); 18 DBMS_OUTPUT.PUT_LINE("Second Number = " || TO_CHAR (second_number)); 19 20 --Swap the values 21 DBMS_OUTPUT.PUT_LINE("Swapping the two values now."); 22 swapn(first_number, second_number); 23 24 --Display the results 25 DBMS_OUTPUT.PUT_LINE("First Number = " || to_CHAR (first_number)); 26 DBMS_OUTPUT.PUT_LINE("Second Number = " || to_CHAR (second_number)); 27 END; 28 /
First Number = 10 Second Number = 20 Swapping the two values now. First Number = 20 Second Number = 10 PL/SQL procedure successfully completed. SQL></source>
Execute a procedure
<source lang="sql">
SQL> set serveroutput on SQL> CREATE or replace PROCEDURE my_first_proc IS
2 greetings VARCHAR2(20); 3 BEGIN 4 greetings := "Hello World"; 5 dbms_output.put_line(greetings); 6 END my_first_proc; 7 /
SQL> SQL> EXECUTE my_first_proc; Hello World PL/SQL procedure successfully completed. SQL> SQL> BEGIN
2 my_first_proc; 3 END; 4 /
Hello World PL/SQL procedure successfully completed. SQL> SQL></source>
Forward Referencing
<source lang="sql">
SQL> SQL> DECLARE
2 PROCEDURE b (caller VARCHAR2); -- This is a forward referencing stub. 3 PROCEDURE a (caller VARCHAR2) IS 4 procedure_name VARCHAR2(1) := "A"; 5 BEGIN 6 dbms_output.put_line("Procedure "A" called by ["||caller||"]"); 7 b(procedure_name); 8 END; 9 PROCEDURE b (caller VARCHAR2) IS 10 procedure_name VARCHAR2(1) := "B"; 11 BEGIN 12 dbms_output.put_line("Procedure "B" called by ["||caller||"]"); 13 END; 14 BEGIN 15 a("Main"); 16 END; 17 /
Procedure "A" called by [Main] Procedure "B" called by [A] PL/SQL procedure successfully completed. SQL></source>
Insert debug line to the stored procedure with DBMS_OUTPUT.PUT_LINE
<source lang="sql">
SQL> SQL> SQL> set serveroutput on SQL> set echo on SQL> SQL> -- create demo table SQL> create table Employee(
2 ID VARCHAR2(4 BYTE) NOT NULL primary key, 3 First_Name VARCHAR2(10 BYTE), 4 Last_Name VARCHAR2(10 BYTE), 5 Start_Date DATE, 6 End_Date DATE, 7 Salary Number(8,2), 8 City VARCHAR2(10 BYTE), 9 Description VARCHAR2(15 BYTE) 10 ) 11 /
Table created. SQL> SQL> -- prepare data SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values ("01","Jason", "Martin", to_date("19960725","YYYYMMDD"), to_date("20060725","YYYYMMDD"), 1234.56, "Toronto", "Programmer") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("02","Alison", "Mathews", to_date("19760321","YYYYMMDD"), to_date("19860221","YYYYMMDD"), 6661.78, "Vancouver","Tester") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("03","James", "Smith", to_date("19781212","YYYYMMDD"), to_date("19900315","YYYYMMDD"), 6544.78, "Vancouver","Tester") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("04","Celia", "Rice", to_date("19821024","YYYYMMDD"), to_date("19990421","YYYYMMDD"), 2344.78, "Vancouver","Manager") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("05","Robert", "Black", to_date("19840115","YYYYMMDD"), to_date("19980808","YYYYMMDD"), 2334.78, "Vancouver","Tester") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("06","Linda", "Green", to_date("19870730","YYYYMMDD"), to_date("19960104","YYYYMMDD"), 4322.78,"New York", "Tester") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("07","David", "Larry", to_date("19901231","YYYYMMDD"), to_date("19980212","YYYYMMDD"), 7897.78,"New York", "Manager") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("08","James", "Cat", to_date("19960917","YYYYMMDD"), to_date("20020415","YYYYMMDD"), 1232.78,"Vancouver", "Tester") 3 /
1 row created. SQL> SQL> SQL> SQL> -- display data in the table SQL> select * from Employee
2 /
ID FIRST_NAME LAST_NAME START_DAT END_DATE SALARY CITY DESCRIPTION
---------- ---------- --------- --------- ---------- ---------- ---------------
01 Jason Martin 25-JUL-96 25-JUL-06 1234.56 Toronto Programmer 02 Alison Mathews 21-MAR-76 21-FEB-86 6661.78 Vancouver Tester 03 James Smith 12-DEC-78 15-MAR-90 6544.78 Vancouver Tester 04 Celia Rice 24-OCT-82 21-APR-99 2344.78 Vancouver Manager 05 Robert Black 15-JAN-84 08-AUG-98 2334.78 Vancouver Tester 06 Linda Green 30-JUL-87 04-JAN-96 4322.78 New York Tester 07 David Larry 31-DEC-90 12-FEB-98 7897.78 New York Manager 08 James Cat 17-SEP-96 15-APR-02 1232.78 Vancouver Tester 8 rows selected. SQL> SQL> CREATE OR REPLACE PROCEDURE emp_change_s (i_emp_id IN VARCHAR2) AS
2 BEGIN 3 UPDATE employee set City = "New" WHERE id = i_emp_id; 4 5 DBMS_OUTPUT.PUT_LINE ("updated "); 6 END emp_change_s; 7 /
Procedure created. SQL> SQL> call emp_change_s("01"); updated Call completed. SQL> SQL> select * from employee;
ID FIRST_NAME LAST_NAME START_DAT END_DATE SALARY CITY DESCRIPTION
---------- ---------- --------- --------- ---------- ---------- ---------------
01 Jason Martin 25-JUL-96 25-JUL-06 1234.56 New Programmer 02 Alison Mathews 21-MAR-76 21-FEB-86 6661.78 Vancouver Tester 03 James Smith 12-DEC-78 15-MAR-90 6544.78 Vancouver Tester 04 Celia Rice 24-OCT-82 21-APR-99 2344.78 Vancouver Manager 05 Robert Black 15-JAN-84 08-AUG-98 2334.78 Vancouver Tester 06 Linda Green 30-JUL-87 04-JAN-96 4322.78 New York Tester 07 David Larry 31-DEC-90 12-FEB-98 7897.78 New York Manager 08 James Cat 17-SEP-96 15-APR-02 1232.78 Vancouver Tester 8 rows selected. SQL> SQL> -- clean the table SQL> drop table Employee
2 /
Table dropped. SQL> SQL></source>
Listing Stored Procedure Information
Oracle provides several data dictionary views that provide information about procedures that are currently stored in your schema:
- all_errors: A list of current errors on all objects accessible to the user
- all_source: Text source of all stored objects accessible to the user
- user_objects:A list of all the objects the current user has access to
- dba_errors:Current errors on all stored objects in the database
- dba_object_size:All PL/SQL objects in the database
- dba_source:Text source of all stored objects in the database
- user_errors:Current errors on all a user"s stored objects
- user_source:Text source of all stored objects belonging to the user
- user_object_size:User"s PL/SQL objects
<source lang="sql">
SELECT object_name, object_type from user_objects WHERE status = "INVALID";</source>
Pass ROWTYPE to a procedure
<source lang="sql">
SQL> SQL> SQL> SQL> -- create demo table SQL> create table Employee(
2 ID VARCHAR2(4 BYTE) NOT NULL primary key, 3 First_Name VARCHAR2(10 BYTE), 4 Last_Name VARCHAR2(10 BYTE), 5 Start_Date DATE, 6 End_Date DATE, 7 Salary Number(8,2), 8 City VARCHAR2(10 BYTE), 9 Description VARCHAR2(15 BYTE) 10 ) 11 /
Table created. SQL> SQL> -- prepare data SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values ("01","Jason", "Martin", to_date("19960725","YYYYMMDD"), to_date("20060725","YYYYMMDD"), 1234.56, "Toronto", "Programmer") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("02","Alison", "Mathews", to_date("19760321","YYYYMMDD"), to_date("19860221","YYYYMMDD"), 6661.78, "Vancouver","Tester") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("03","James", "Smith", to_date("19781212","YYYYMMDD"), to_date("19900315","YYYYMMDD"), 6544.78, "Vancouver","Tester") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("04","Celia", "Rice", to_date("19821024","YYYYMMDD"), to_date("19990421","YYYYMMDD"), 2344.78, "Vancouver","Manager") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("05","Robert", "Black", to_date("19840115","YYYYMMDD"), to_date("19980808","YYYYMMDD"), 2334.78, "Vancouver","Tester") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("06","Linda", "Green", to_date("19870730","YYYYMMDD"), to_date("19960104","YYYYMMDD"), 4322.78,"New York", "Tester") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("07","David", "Larry", to_date("19901231","YYYYMMDD"), to_date("19980212","YYYYMMDD"), 7897.78,"New York", "Manager") 3 /
1 row created. SQL> insert into Employee(ID, First_Name, Last_Name, Start_Date, End_Date, Salary, City, Description)
2 values("08","James", "Cat", to_date("19960917","YYYYMMDD"), to_date("20020415","YYYYMMDD"), 1232.78,"Vancouver", "Tester") 3 /
1 row created. SQL> SQL> SQL> SQL> -- display data in the table SQL> select * from Employee
2 /
ID FIRST_NAME LAST_NAME START_DAT END_DATE SALARY CITY DESCRIPTION
---------- ---------- --------- --------- ---------- ---------- ---------------
01 Jason Martin 25-JUL-96 25-JUL-06 1234.56 Toronto Programmer 02 Alison Mathews 21-MAR-76 21-FEB-86 6661.78 Vancouver Tester 03 James Smith 12-DEC-78 15-MAR-90 6544.78 Vancouver Tester 04 Celia Rice 24-OCT-82 21-APR-99 2344.78 Vancouver Manager 05 Robert Black 15-JAN-84 08-AUG-98 2334.78 Vancouver Tester 06 Linda Green 30-JUL-87 04-JAN-96 4322.78 New York Tester 07 David Larry 31-DEC-90 12-FEB-98 7897.78 New York Manager 08 James Cat 17-SEP-96 15-APR-02 1232.78 Vancouver Tester 8 rows selected. SQL> SQL> CREATE OR REPLACE PROCEDURE update_emp (emp_rec employee%ROWTYPE) IS
2 BEGIN 3 UPDATE employee 4 SET start_date = emp_rec.start_date + 100 5 WHERE id = emp_rec.id; 6 END update_emp; 7 /
Procedure created. SQL> SQL> SQL> DECLARE
2 a employee%ROWTYPE; 3 BEGIN 4 a.id := "01"; 5 update_emp(a); 6 END; 7 /
PL/SQL procedure successfully completed. SQL> SELECT * FROM employee;
ID FIRST_NAME LAST_NAME START_DAT END_DATE SALARY CITY DESCRIPTION
---------- ---------- --------- --------- ---------- ---------- ---------------
01 Jason Martin 25-JUL-06 1234.56 Toronto Programmer 02 Alison Mathews 21-MAR-76 21-FEB-86 6661.78 Vancouver Tester 03 James Smith 12-DEC-78 15-MAR-90 6544.78 Vancouver Tester 04 Celia Rice 24-OCT-82 21-APR-99 2344.78 Vancouver Manager 05 Robert Black 15-JAN-84 08-AUG-98 2334.78 Vancouver Tester 06 Linda Green 30-JUL-87 04-JAN-96 4322.78 New York Tester 07 David Larry 31-DEC-90 12-FEB-98 7897.78 New York Manager 08 James Cat 17-SEP-96 15-APR-02 1232.78 Vancouver Tester 8 rows selected. SQL> SQL> SQL> -- clean the table SQL> drop table Employee
2 /
Table dropped. SQL> SQL></source>
Procedures
You can create a procedure that contains a group of SQL and PL/SQL statements.
Procedures allow you to centralize your business logic in the database.
Procedures may be used by any program that accesses the database.
You create a procedure using the CREATE PROCEDURE statement.
The simplified syntax for the CREATE PROCEDURE statement is as follows:
<source lang="sql">
CREATE [OR REPLACE] PROCEDURE procedure_name [(parameter_name [IN | OUT | IN OUT] type [, ...])] {IS | AS} BEGIN
procedure_body
END procedure_name;</source>
Storing PL/SQL procedure in the Database
<source lang="sql">
create [or replace] procedure procedure name (parameters) is
... begin ... end;</source>
Wrapping a task into a procedure
<source lang="sql">
SQL> SQL> SQL> SQL> declare
2 v VARCHAR2(50):= "I just printed my <in> line!"; 3 procedure p_print(i_string in VARCHAR2, i_replace in VARCHAR2 := "new") is 4 begin 5 DBMS_OUTPUT.put_line(replace(i_string,"<in>", i_replace)); 6 end; 7 begin 8 p_print (v,"first"); 9 p_print (v,"second"); 10 p_print (v); 11 end; 12 /
I just printed my first line! I just printed my second line! I just printed my new line! PL/SQL procedure successfully completed. SQL></source>