Oracle PL/SQL/Trigger/Triggerable Actions
Check user name in a trigger
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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>
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Log all triggerable action: iinsert, update and delete to a log table
<source lang="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 /
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>
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