Oracle PL/SQL/Trigger/Triggerable Actions
Check user name in a trigger
SQL>
SQL>
SQL> create table foo( a number );
Table created.
SQL>
SQL> create or replace trigger biud_foo
2 before insert or update or delete
3 on foo
4 begin
5 if user not in ( "CLBECK", "SDILLON" ) then raise_application_error( -20001,"You do not have access to modify this table." );
6 end if;
7 end;
8 /
Trigger created.
SQL>
SQL> insert into foo (a) VALUES (1);
insert into foo (a) VALUES (1)
*
ERROR at line 1:
ORA-20001: You do not have access to modify this table.
ORA-06512: at "sqle.BIUD_FOO", line 2
ORA-04088: error during execution of trigger "sqle.BIUD_FOO"
SQL>
SQL> drop table foo;
Table dropped.
SQL>
Log all triggerable action: iinsert, update and delete to a log table
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 /
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 /
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 /
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 /
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 /
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 /
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 /
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 /
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 /
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
SQL>
SQL>
SQL>
SQL> create table employees_copy as select * from employee;
SQL>
SQL> create table employees_log(
2 who varchar2(30),
3 action varchar2(100),
4 when date );
SQL>
SQL>
SQL> create or replace trigger biud_employees_copy
2 before insert or update or delete
3 on employees_copy
4 begin
5 state_package.rows_changed := 0;
6 end;
7 /
SQL>
SQL> create trigger biudfer_employees_copy
2 before insert or update or delete
3 on employees_copy
4 for each row
5 declare
6 l_action employees_log.action%type;
7 begin
8 if INSERTING then
9 l_action := "Insert";
10 elsif UPDATING then
11 l_action := "Update";
12 elsif DELETING then
13 l_action := "Delete";
14 else
15 raise_application_error( -20001,
16 "You should never ever get this error." );
17 end if;
18
19 state_package.rows_changed := state_package.rows_changed + 1;
20
21 if UPDATING( "SALARY" ) then
22 l_action := l_action || " - " ||
23 "Salary for id " || :old.id ||
24 " changed from " || :old.salary ||
25 " to " || :new.salary;
26 end if;
27
28 insert into employees_log(
29 who, action, when )
30 values(
31 user, l_action, sysdate );
32 end;
33 /
SQL>
SQL> create trigger aiud_employees_copy
2 after insert or update or delete
3 on employees_copy
4 declare
5 l_action employees_log.action%type;
6 begin
7 if INSERTING then
8 l_action := state_package.rows_changed || " were " || "inserted";
9 elsif UPDATING then
10 l_action := state_package.rows_changed || " were " || "updated";
11 elsif DELETING then
12 l_action := state_package.rows_changed || " were " || "deleted";
13 else
14 raise_application_error( -20001,
15 "You should never ever get this error." );
16 end if;
17
18 insert into employees_log(
19 who, action, when )
20 values(
21 user, l_action, sysdate );
22 end;
23 /
SQL>
SQL> update employees_copy set salary = salary * 0.95;
SQL>
SQL>
SQL> select * from employees_log;
WHO ACTION WHEN
------------------------------ ---------------------------------------------------------------------------------------------------- ---------
sqle Update - Salary for id 01 changed from 1234.56 to 1172.83 09-SEP-06
sqle Update - Salary for id 02 changed from 6661.78 to 6328.69 09-SEP-06
sqle Update - Salary for id 03 changed from 6544.78 to 6217.54 09-SEP-06
sqle Update - Salary for id 04 changed from 2344.78 to 2227.54 09-SEP-06
sqle Update - Salary for id 05 changed from 2334.78 to 2218.04 09-SEP-06
sqle Update - Salary for id 06 changed from 4322.78 to 4106.64 09-SEP-06
sqle Update - Salary for id 07 changed from 7897.78 to 7502.89 09-SEP-06
sqle Update - Salary for id 08 changed from 1232.78 to 1171.14 09-SEP-06
sqle 8 were updated 09-SEP-06
SQL>
SQL>
SQL> drop table employees_copy;
SQL>
SQL> drop table employees_log;
SQL>
SQL> -- clean the table
SQL> drop table Employee
2 /
SQL>
SQL>
SQL>
SQL>