Oracle trigger to update a column value in the same table - oracle

I am in the need of a trigger which will fire on any insert or updates on the specific table and while inserting or updating will substitute a credit card number column of the new row to something bogus such as "1111 1111 1111 1111"
Here is what I cooked up but it doesn't seem to work.
CREATE or REPLACE TRIGGER trigger_name AFTER INSERT ON table1
FOR EACH ROW
BEGIN
update table1 set cc_number_field = '11';
END;
I am on Oracle 10 if that matters.

It's much easier to manipulate the incoming :NEW line with a "before" trigger:
CREATE OR REPLACE TRIGGER table1_cc_trigger
BEFORE INSERT OR UPDATE ON table1
FOR EACH ROW
BEGIN
:NEW.cc_number_field := '1111 1111 1111 1111';
END;
/

Not tested:
CREATE OR REPLACE TRIGGER t
BEFORE
INSERT on ON table1 FOR EACH ROW
begin
:new.cc_number_field = '11';
END;
PL/SQL Reference - Triggers

Related

Addition of values in two columns isn't working in PL/SQL ORACLE

So I am trying to add age with price and store the result on another table with the ID of the person who did this. I am able to set the business rule by making the trigger but when I check my second (END) table, there is nothing there.. Here is my code for the trigger:
CREATE OR REPLACE TRIGGER JIM
BEFORE INSERT ON END
FOR EACH ROW ENABLE
DECLARE
V_AGE JIM.AGE%TYPE;
V_PRICE JIM.PRICE%TYPE;
v_prices NUMBER(20);
BEGIN
SELECT AGE,PRICE INTO V_AGE,V_PRICE FROM JIM WHERE ID=:NEW.ID;
v_prices:=V_AGE+V_PRICE;
INSERT INTO END VALUES(:new.ID,v_prices);
END;
However, When I insert values onto the JIM table using the following code:
insert into jim values(4,'Sim',45,100);
nothing actually gets stored on the END table. i am sort of new to triggers and its so confusing. Please let me know what to do. thanls
Don't use a keyword end as a table name, this causes problem during
creation of trigger. I've presumed the table's name as t_end.
I think you are confused on which table to define trigger. It seems
you should define on table jim instead of t_end.
I've presumed you have a sequence named seq_end to populate the id
column of the table t_end
So , your trigger creation statement will be as follows :
create or replace trigger trg_ins_jim before insert on jim for each row
declare
v_id_end t_end.id%type;
v_prices t_end.prices%type;
begin
v_prices := :new.age + :new.price;
v_id_end := seq_end.nextval; insert into t_end values(v_id_end, v_prices);
/* if you have defined sequence for t_end as default value of id column, you may change the upper row as "insert into t_end(prices) values(v_prices);" and there would be no need for "v_id_end" */
end;
and when you issue insert into jim values(4,'Sim',45,100); command, you'll also have values inserted into t_end.
If there is only one table, then the SELECT and the INSERT are redundant.
CREATE OR REPLACE TRIGGER trigger_name
BEFORE INSERT ON table_name
FOR EACH ROW
BEGIN
:NEW.PRICES := :NEW.AGE + :NEW.PRICE;
END;
Possible duplicate

Using INSERT INTO... SELECT in TRIGGER

The question I am going to ask is already there. But I don't have answer for this.
Please refer the below link.
ORACLE TRIGGER INSERT INTO ... (SELECT * ...)
I have around 600 columns in a table. After each insert in this table I need to insert the new row in another backup table.
Please tell how to use "INSERT INTO TABLE_NAME2 SELECT * FROM TABLE_NAME1" query in trigger.
Note: Without specifying columns in insert or select clause
Structure of both table is same. Specifying all the column name in trigger is difficult and also if new columns added, we need to add in trigger as well.
SQL> CREATE or REPLACE TRIGGER emp_after_insert AFTER INSERT ON emp
FOR EACH ROW
DECLARE
BEGIN
insert into emp_backup values (:new.empid, :new.fname, :new.lname);
DBMS_OUTPUT.PUT_LINE('Record successfully inserted into emp_backup table');
END;
reference:
http://www.tech-recipes.com/rx/19839/oracle-using-the-after-insert-and-after-update-triggers/
You should use COMPOUND TRIGGER. This trigger should look like this:
CREATE OR REPLACE TRIGGER t_copy_table1
FOR INSERT ON table1
COMPOUND TRIGGER
v_id number;
BEFORE EACH ROW IS
BEGIN
v_id := :new.id;
END BEFORE EACH ROW;
AFTER STATEMENT IS
BEGIN
insert into table2 select * from table1 where id=v_id;
END AFTER STATEMENT;
END t_copy_table1;

Is before update trigger will fire if same values are updating into a row of column

I am using before update trigger for each row on table, say emp_table to update one column modifid_date before loading into table. If I am going to update the table with same/existing values of a row, then is this trigger going to fire or not?
condition in trigger:
:new.modifid_dt := sysdate;
Table Values before update: john (name),4867 (id),20-04-2016 (modifid_dt)
Table values now going to update: john (name),4867 (id)
Your trigger will be fired, no matter the values you are using; for example:
SQL> create table testTrigger ( a number)
2 /
Table created.
SQL> CREATE OR REPLACE TRIGGER before_update_trigger
2 before update on testTrigger
3 for each row
4 begin
5 dbms_output.put_line('Trigger fired!');
6 end;
7 /
Trigger created.
SQL> insert into testTrigger values (10);
1 row created.
SQL>
SQL>
SQL> update testTrigger set a = 10;
Trigger fired!
1 row updated.
SQL> update testTrigger set a = 11;
Trigger fired!
1 row updated.
SQL>
If you want avoid "false" firing you should write trigger like this:
create or replace trigger trigger1
before update on tst
for each row
begin
IF :new.t_key != :old.t_key AND ... THEN
dbms_output.put_line('Trigger fired!');
END IF;
end;
But beware of NULL values, of course.
New or existing values - no matter, anyway you'll perform an update so trigger will fire.

Concatenate String with a column in trigger

I have a table called TBL_CAS. In that, FLD_ID as auto increment column and another column is called FLD_CAS_CODE. Now I need to add CAS- as a prefix to FLD_ID and Insert into FLD_CAS_CODE. I need to do this in trigger. I was tried with the below code, But the data in not inserting, What is the problem ?
CREATE OR REPLACE TRIGGER TBL_CAS_TRG
BEFORE INSERT ON TBL_CAS
FOR EACH ROW
BEGIN
:NEW.FLD_CAS_CODE := TO_CHAR ('CAS')||'-'||:NEW.FLD_ID;
END;
I mean `"cas-"+"fld_id"="cas-fld_id"'
You don't need to put TO_CHAR() around things which are already charcater datatypes. But you should cast the numeric identifier (rather than relying on implicit conversion):
:NEW.FLD_CAS_CODE := 'CAS-'||TRIM(TO_CHAR (:NEW.FLD_ID));
which part isn't working exactly? as your trigger seem to work just fine.
SQL> create table TBL_CAS( FLD_ID number, FLD_CAS_CODE varchar2(20));
Table created.
SQL> CREATE OR REPLACE TRIGGER TBL_CAS_TRG
2 BEFORE INSERT ON TBL_CAS
3 FOR EACH ROW
4 BEGIN
5 :NEW.FLD_CAS_CODE := TO_CHAR ('CAS')||'-'||:NEW.FLD_ID;
6 END;
7 /
Trigger created.
SQL> insert into TBL_CAS (fld_id) values (1001);
1 row created.
SQL> select * From TBL_CAS;
FLD_ID FLD_CAS_CODE
---------- --------------------
1001 CAS-1001
SQL>
This will also work fine:
CREATE OR REPLACE TRIGGER TBL_AREA_CODES_TRG
BEFORE INSERT ON TBL_AREA_CODES
FOR EACH ROW
BEGIN
:NEW.OBRM_AREA_CODE := :NEW.STATE_CODE ||'-'||:NEW.DIST_CODE ||'-'||:NEW.CITY_CODE ||'-'||:NEW.AREA_CODE ;
END;

Oracle 'statement level' Trigger

I want to create a Statement level Trigger which means I want to insert only one record into table EMP_AUDIT when 1 or more rows are inserted into table EMP. For example: if I have 10 records inserted into EMP, then only 1 record should be inserted into EMP_AUDIT table.
There are no constraints on columns. (i.e. can be NULL)
I tried to use the following trigger but it gives me the Error(2,2): PL/SQL: SQL Statement ignored
Error(2,14): PL/SQL: ORA-00947: not enough values
CREATE OR REPLACE
TRIGGER TRIG_EMP AFTER INSERT ON EMP
BEGIN
INSERT INTO EMP_AUDIT
VALUES (TRANID,EMPNUM,SYSDATE);
END;
CREATE TABLE EMP
(TRANID NUMBER,
EMPNUM VARCHAR2(100),
EMPLOC VARCHAR2(100));
CREATE TABLE EMP_AUDIT
(EVENTID NUMBER,
EMPNUM VARCHAR2(100),
ENTRDATE DATE);
The statement-level trigger (which you have) cannot see the data that was inserted. After all, if there were 10 rows inserted, what values should the columns be for your audit table?
You need a row-level trigger for this to work, e.g.:
CREATE OR REPLACE
TRIGGER TRIG_EMP
AFTER INSERT ON EMP
FOR EACH ROW
BEGIN
INSERT INTO EMP_AUDIT
VALUES (:NEW.TRANID,:NEW.EMPNUM,:NEW.SYSDATE);
END;
Use this piece of code:
CREATE OR REPLACE TRIGGER
TRIG_EMP
AFTER INSERT ON EMP
FOR EACH ROW
BEGIN
INSERT INTO EMP_AUDIT
VALUES (:NEW.TRANID,:NEW.EMPNUM,:NEW.SYSDATE);
END;

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