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> -- 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> PROMPT ** Set the PLSQL_WARNING level to DISABLE:ALL
** Set the PLSQL_WARNING level to DISABLE:ALL
SQL>
SQL> CALL DBMS_WARNING.SET_WARNING_SETTING_STRING('DISABLE:ALL', 'SESSION');
Call completed.
SQL>
SQL> --Create a procedure that does not include an EXIT WHEN statement in the loop
SQL>
SQL> CREATE OR REPLACE PROCEDURE compile_warning
2 AS
3
4 v_title VARCHAR2(100);
5
6 CURSOR dbms_warning_cur
7 IS
8 SELECT id
9 FROM employee;
10
11 BEGIN
12
13 OPEN dbms_warning_cur;
14
15 LOOP
16 FETCH dbms_warning_cur INTO v_title;
17 -- there should be a line to exit here
18 -- like EXIT WHEN dbms_warning_cur%NOTFOUND
19
20 DBMS_OUTPUT.PUT_LINE('Titles Available: '||v_title);
21
22 END LOOP;
23
24 CLOSE dbms_warning_cur;
25
26 END;
27 /
Procedure created.
SQL>
SQL> PROMPT ** The procedure compiles fine
** The procedure compiles fine
SQL>
SQL> SET SERVEROUTPUT ON ESCAPE OFF
SQL>
SQL> CALL DBMS_WARNING.SET_WARNING_SETTING_STRING('ENABLE:ALL', 'SESSION');
Call completed.
SQL>
SQL> SELECT DBMS_WARNING.GET_WARNING_SETTING_STRING() WARNING_LEVEL FROM dual;
WARNING_LEVEL
------------------------
ENABLE:ALL
1 row selected.
SQL> -- Now recompile the same procedure
SQL>
SQL> ALTER PROCEDURE compile_warning COMPILE;
SP2-0805: Procedure altered with compilation warnings
SQL>
SQL> -- This shows that there is a warning message. Type SHOW ERRORS to see what the problem is.
SQL>
SQL> SHOW ERRORS
Errors for PROCEDURE COMPILE_WARNING:
LINE/COL ERROR
------------------------------------------
24/4 PLW-06002: Unreachable code
SQL>
SQL> -- clean the table
SQL> drop table Employee
2 /
Table dropped.