I need some assistance with troubleshooting the trigger that I'm trying to create/use for logging updates and inserts on a table.
I'm using a customers_history table to track all the changes being made on the customers table.
CREATE TABLE customers (
custID INTEGER PRIMARY KEY,
custFName VARCHAR2(30),
custLName VARCHAR2(30),
custState CHAR(20),
custZip NUMBER(5)
);
-- log inserts and updates on customers table
CREATE TABLE customers_history (
histID INTEGER PRIMARY KEY,
cID INTEGER,
cFName VARCHAR2(30),
cLName VARCHAR2(30),
cState CHAR(20),
cZip NUMBER(5)
);
Also, for the histID I'm using a sequence to auto increment the histID on customers_history table.
CREATE SEQUENCE ch_seq
MINVALUE 1
START WITH 1
INCREMENT BY 1;
CREATE OR REPLACE TRIGGER audit_customers
BEFORE UPDATE
OR INSERT ON customers
FOR EACH ROW
BEGIN
INSERT INTO customers_history(histID,cID,cFName,cLName,cState,cZip)
VALUES(ch_seq.nextval,:NEW.custID,:NEW.custFName,:NEW.custLName,
:NEW.custState,:NEW.custZip);
END;
/
I have been inserting two rows on customers prior to creating the trigger, and they work fine. After I create the trigger, it will not allow me to insert anymore rows on customers and it also throws the ORA-04098: trigger 'SYSTEM.AUDIT_CUSTOMERS' is invalid and failed re-validation 04098. 00000 - "trigger '%s.%s' is invalid and failed re-validation" error message.
I've tried to see if there is any code errors using select * from user_errors where type = 'TRIGGER' and name = 'audit_customers'; and it returned no lines. Not sure if that helps or not. Thanks.
you have created your trigger for multiple DML operations (Insert and Update) so you need to specipy the DML operation by using IF INSERTING THEN....END IF; and IF UPDATING THEN....END IF; for example:
CREATE OR REPLACE TRIGGER audit_customers
BEFORE UPDATE
OR INSERT ON customers
FOR EACH ROW
BEGIN
IF INSERTING THEN
INSERT INTO customers_history(histID,cID,cFName,cLName,cState,cZip)
VALUES(ch_seq.nextval,:NEW.custID,:NEW.custFName,:NEW.custLName,
:NEW.custState,:NEW.custZip);
END IF;
END;
/
I went through and changed a couple things and it seems to work for both insert and update operations. I dropped the tables, sequence, and trigger, then did the tried the following code and it works now. Thank you all for your time and inputs!
CREATE TABLE customers (
custID INTEGER,
custFName VARCHAR2(30),
custLName VARCHAR2(30),
custState CHAR(20),
custZip NUMBER(5)
);
CREATE TABLE customers_history (
histID INTEGER,
cID INTEGER,
cFName VARCHAR2(30),
cLName VARCHAR2(30),
cState CHAR(20),
cZip NUMBER(5)
);
CREATE OR REPLACE TRIGGER audit_customers
BEFORE UPDATE
OR INSERT ON customers
FOR EACH ROW
BEGIN
INSERT INTO customers_history(
histID,
cID,
cFName,
cLName,
cState,
cZip
)
VALUES(
ch_seq.nextval,
:new.custID,
:new.custFName,
:new.custLName,
:new.custState,
:new.custZip
);
END;
/
I used the same sequence code as before, added a couple of rows, and it worked. Then I altered the two tables, by adding the primary keys,
ALTER TABLE customers ADD PRIMARY KEY(custID);
ALTER TABLE customers_history ADD PRIMARY KEY(histID);
inserted a couple other columns, modified a few rows, and it still worked. I'm a happy camper, although I'm not certain what or how it actually got fixed.
Related
I got a table Location
CREATE TABLE Location (
idL INTEGER,
City VARCHAR2(15) NOT NULL,
Street VARCHAR2(35) NOT NULL,
Nation CHAR(6) NOT NULL,
CONSTRAINT PK_idL PRIMARY KEY(idL)
);
And a table Person
CREATE TABLE Person(
p_Name VARCHAR2(20) NOT NULL,
p_Surname VARCHAR2(20) NOT NULL,
idP INTEGER,
b_Date DATE NOT NULL,
id_PL INTEGER,
CONSTRAINT PK_idP PRIMARY KEY(idP),
CONSTRAINT FK_idPL FOREIGN KEY(id_PL) REFERENCES Location(idL)
);
I calculate the primary key "automatically" as it follows:
CREATE SEQUENCE seq_loc_pk
start with 1
increment by 1;
CREATE OR REPLACE TRIGGER auto_pk_loc
BEFORE INSERT ON Location
FOR EACH ROW
BEGIN
:new.idL := seq_loc_pk.nextval;
END;
/
Now I want to insert the residence for a new person (after I've created the right view of course) with an instead of trigger like this:
CREATE OR REPLACE TRIGGER newperson
INSTEAD OF INSERT ON Residence
FOR EACH ROW
DECLARE
nl Loc.idL%TYPE;
BEGIN
ALTER TRIGGER auto_pk_loc DISABLE; -- Error
nl := seq_loc_pk.nextval;
:NEW.idL := nl;
INSERT INTO Location VALUES(:NEW.City,:NEW.Street,:NEW.Nation);
INSERT INTO Patient VALUES(:NEW.P_Name,:NEW.P_Surname,:NEW.B_Date,,nl);
ALTER TRIGGER auto_pk_loc ENABLE;
END;
/
I thought about disabling and enabling the trigger auto_pk_loc so that it doesn't create extra values for no reason, but I think this is not the right way to do it? What is it though? Thanks for whoever answers.
You can do this by placing it in execute immedaite:
BEGIN
execute immedidate 'ALTER TRIGGER auto_pk_loc DISABLE';
nl := seq_loc_pk.nextval;
:NEW.idL := nl;
INSERT INTO Location VALUES(:NEW.City,:NEW.Street,:NEW.Nation);
INSERT INTO Patient VALUES(:NEW.P_Name,:NEW.P_Surname,:NEW.B_Date,,nl);
execute immedidate 'ALTER TRIGGER auto_pk_loc ENABLE';
END;
/
But this will cause you all sorts of issues; DDL commits so you'll have to make this an autonomous transaction and you'll hit concurrency problems. This is best avoided.
A better method is to use the returning clause to fetch the value you just inserted:
BEGIN
INSERT INTO Location VALUES(:NEW.City,:NEW.Street,:NEW.Nation)
returning idl into nl;
INSERT INTO Patient VALUES(:NEW.P_Name,:NEW.P_Surname,:NEW.B_Date,nl);
END;
/
Though as #astentx noted, you probably want to use merge to avoid having duplicate locations. This doesn't support returing, so you'll have to use some combination of insert+update instead.
Finally - assuming you're on 12c or higher - it's better to use an identity column or sequence default to auto-generate the location IDs over a trigger.
Please, help!
I have trigger:
CREATE TRIGGER check_reservation BEFORE INSERT ON order
FOR EACH ROW
DECLARE mistake INTEGER;
BEGIN
SELECT count(*) INTO mistake FROM order join reserving
on id_order = reserving.order_id_order
WHERE reserving.room_num_room=:new.room_num_room
AND (order.reservation_from < :new.reservation_from AND :new.reservation_from < order.reservation_to) OR
(order.reservation_from < :new.reservation_from AND :new.reservation_to < order.reservation_to) OR
(:new.reservation_from <= order.reservation_from AND order.reservation_to <= :new.reservation_to);
IF mistake>0 THEN
raise_application_error(-20001,'reservation already exists');
END IF;
END;
The idea of the trigger is not to allow make a reservation on already booked room. When I run it I had check compiler log error message. How can I change trigger?
I have following tables:
CREATE TABLE order (
id_order CHAR(100) NOT NULL,
reservation_from DATE NOT NULL,
reservation_to DATE NOT NULL,
);
ALTER TABLE order ADD CONSTRAINT order_pk PRIMARY KEY ( id_order );
CREATE TABLE room (
num_room CHAR(100) NOT NULL,
type VARCHAR2(100) NOT NULL,
);
ALTER TABLE room ADD CONSTRAINT room_pk PRIMARY KEY ( num_room );
CREATE TABLE reserving (
room_num_room CHAR(100) NOT NULL,
order_id_order CHAR(100) NOT NULL
);
ALTER TABLE reserving ADD CONSTRAINT reserving_pk PRIMARY KEY ( room_num_room,
order_id_order );
ALTER TABLE reserving
ADD CONSTRAINT reserving_order_fk FOREIGN KEY ( order_id_order )
REFERENCES order ( id_order );
ALTER TABLE reserving
ADD CONSTRAINT reserving_room_fk FOREIGN KEY ( room_num_room )
REFERENCES room ( num_room );
I tried recreating the trigger with the statements above. The statements failed with several errors, it looks as if they were not tested before posting them as question. Please take some time posting a quality question.
Example:
CREATE TABLE room (
num_room CHAR(100) NOT NULL,
type VARCHAR2(100) NOT NULL, << this trailing comma makes this statement fail.
);
After fixing all errors I ran the "CREATE TRIGGER" and it errored out with
PLS-00049: bad bind variable 'NEW.ROOM_NUM_ROOM'
That is because the column ROOM_NUM_ROOM does not exist in the "ORDER" table.
If I remove the reference to 'NEW.ROOM_NUM_ROOM' the trigger compiles successfully.
However, as gsalem pointed out, this will not work because it will raise a mutating table error. In the trigger code you cannot execute DML referencing the table that the trigger is on. There is plenty of documentation on how to avoid mutating table errors.
When an insert is made to Condo_assign I am using multiple triggers to add entries to a reserveError table to indicate what the error was. After they are logged in reserveError I am now attempting to use another trigger to delete the record from condo_assign that caused the problem. Basically, the erroneous insert should be logged in ReserveError and Deleted from Condo_assign. The problem is that while my delete trigger compiles and causes no problems, it doesn't appear to do anything. when I select * from condo_assign the erroneous entries are still there.
Condo_Assign table:
CREATE TABLE Condo_Assign (
MID INT
, RID VARCHAR2(3)
, CONSTRAINT Condo_Assign Primary Key (MID,RID)
, CONSTRAINT MID_Assign_FK Foreign Key (MID) references SkiClub (MID)
, CONSTRAINT RID_Assign_FK Foreign Key (RID) references Condo_Reservation (RID)
);
reserveError Table:
CREATE TABLE ReserveError (
Err INT PRIMARY KEY
, MID INT
, RID VARCHAR2(3)
, errorDate DATE
, errorCode VARCHAR2(6)
, errorMsg VARCHAR2(60)
, CONSTRAINT Error_MID_FK FOREIGN KEY (MID) REFERENCES SkiClub
, CONSTRAINT Error_RID_FK FOREIGN KEY (RID) REFERENCES Condo_Reservation
);
Procedure that causes trigger to fire:
CREATE OR REPLACE Procedure addCondo_Assign
(
inMID in Condo_Assign.MID%type
, inRID in Condo_Assign.RID%type
, inPaymentDate in Payment.PaymentDate%type
, inPayment in Payment.Payment%type
)
is
begin
insert into Condo_Assign (MID,RID) values (inMid,inRid);
IF inPayment >= 50 then
insert into Payment (MID,RID,PaymentDate,Payment) values (inMID,inRID,inPaymentDate,inPayment);
ELSE
raise_application_error(-20088,'Deposit less than 50');
end if;
exception
when others then
raise_application_error(-20005,'Cannot add to entry to Condo_Assign Table.');
end addCondo_Assign;
/
Trigger that writes to ReserveError table
-- Trigger to prevent gender mismatchs in room assignment
CREATE OR REPLACE TRIGGER Gender_Assign_Trigger
BEFORE INSERT ON Condo_Assign
FOR EACH ROW
DECLARE
Room_Gender Char(1);
Guest_Gender Char(1);
BEGIN
SELECT Gender
INTO Room_Gender
From Condo_Reservation
WHERE RID = :new.RID;
SELECT Gender
INTO Guest_Gender
FROM SkiClub
WHERE MID = :new.MID;
IF Room_Gender = 'M' AND Guest_Gender = 'F' THEN
addReserveError(:new.MID,:new.RID,SYSDATE,'g00001','Female guest assigned to male room');
ELSIF Room_Gender = 'F' AND Guest_Gender = 'M' THEN
addReserveError(:new.MID,:new.RID,SYSDATE,'g00002','Male guest assigned to female room');
END IF;
END Gender_Assign_Trigger;
/
Trigger that should delete entry from condo_assign:
CREATE OR REPLACE TRIGGER Remove_errors_trigger
after Insert on ReserveError
FOR EACH ROW
BEGIN
DELETE FROM Condo_Assign
WHERE MID = :new.MID and RID = :new.RID;
END remove_errors_trigger;
/
The entire process is started in a before insert trigger.
The code that tries to delete the record won't delete anything because the record has not been inserted yet. There is nothing to delete at the time the delete code is being fired.
Usually checks in triggers prevent the insertion of incorrect data throwing an exception. The code inserting the data will have to handle the exception.
But you already have a procedure that handles the insert. It even performs a check on the deposit. Why not handle the gender check there?
Evening, needing assistance regarding triggers.
Within my development environment I have two tables, one containing employee data (which contains various data errors that will be amended via ALTER TABLE) and the log table.
How do i go about designing a trigger that will update multiple rows contained within the log table such as 'issue_status','status_update_date' when ALTER TABLE sql is used to amend the data contained in the first data table?
-- employee table
CREATE TABLE emp(
emp_id INTEGER NOT NULL,
emp_name VARCHAR(30),
emp_postcode VARCHAR(20),
emp_registered DATE,
CONSTRAINT pk_emp PRIMARY KEY (emp_id));
-- SQL for the log table
CREATE TABLE data_log
(issue_id NUMBER(2) NOT NULL,
table_name VARCHAR2(20),
row_name VARCHAR2(20),
data_error_code NUMBER(2),
issue_desc VARCHAR2(50),
issue_date DATE,
issue_status VARCHAR2(20),
status_update_date DATE);
-- example log insert
INSERT INTO data_log( SELECT DI_SEQ.nextval, 'emp', emp.emp_id, '1', 'emp_name case size not UPPER', SYSDATE, 'un-fixed', '' FROM emp WHERE emp_name != UPPER(emp_name));
This is the example of the issue inserted into the log table. All i want to do is if I update the emp table to set 'emp_name' to Upper the trigger will register this update and change the rows 'issue_status' and 'status_update_date' to 'fixed' and the 'sysdate' of when the change was made
I've done some browsing however i'm still struggling to understand, any literature recommendations would be appreciated also.
Thanks in advance for the assistance.
Note that we don't use ALTER TABLE to update the rows of a table as you have mentioned.We use Update statement. Your trigger should be a BEFORE UPDATE TRIGGER like this.
CREATE OR REPLACE TRIGGER trig_emp_upd BEFORE
UPDATE ON emp
FOR EACH ROW
WHEN ( new.emp_name = upper(old.emp_name) )
BEGIN
UPDATE data_log
SET
issue_status = 'fixed',
status_update_date = SYSDATE
WHERE
row_name =:new.emp_id;
END;
/
I am attempting to write a trigger which prevents the insertion into my TA (teaching assistant) table if the student is already taking the class for which they're attempting to become a TA. From what I understand the best way to do this (other than a unique constraint, this has to be a trigger) is through the use of rollback, and I'm also using raiserror.
create or replace trigger CheckTA
after insert
on TA for each row
begin
if exists (select * from Enrolls where Student_ID = :new.Student_ID and Course_ID = :new.Course_ID) then
rollback;
raiserror('TA enrolled in course as student');
end if;
end;
Upon creating the trigger, I'm met with the following errors:
Error(2,2): PL/SQL: Statement ignored
Error(2,5): PLS-00204: function or pseudo-column 'EXISTS' may be used inside a SQL statement only
The trigger still gets created, but it doesn't trigger when improper values are inserted into TA.
Tables:
TA
Create table TA
(
Student_ID int references Student(Student_ID),
Course_ID int references Course(Course_ID),
Courses_taught varchar2(250),
Office_hours varchar2(25)
);
Student
create table Student
(
Student_ID int primary key,
Name varchar2(50),
Start_began int,
Semester_began varchar2(50),
GPA int,
Degree_status varchar2(25),
Degree_type varchar2(50),
Courses_Taken varchar2(250),
JI_list varchar2(250),
Profile_status varchar2(50)
);
Course
create table Course
(
Course_ID int primary key,
Course_Name varchar2(25)
);
Enrolls
create table Enrolls
(
Student_ID int references Student(Student_ID),
Course_ID int references Course(Course_ID)
);
Stored Procedure
This is the SP I use to insert TA values that should trigger the trigger. It doesn't raise errors but I'll put it here in case it's relevant.
create or replace procedure addTA (s_id int, c_id int, course varchar2)
as
begin
insert into TA (Student_ID,Course_ID,Courses_taught)
values (s_id,c_id,course);
end;
Honestly I'm not quite sure what these errors mean, let alone what's causing them, but still I've tried messing with the syntax of raiserror as well as replacing it with raise_application_error with no luck. If anyone could help me resolve or at least explain these errors it would be greatly appreciated. And of course if there is anything obviously wrong with my trigger please let me know.
The error says "function or pseudo-column 'EXISTS' may be used inside a SQL statement only", meaning that you only can use EXISTS inside a SQL statment, while you are using in in a PL/SQL statement.
If you need to check for the existence of some records, you can try something like this:
vNum number;
...
select count(1)
into vNumber
from Enrolls
where Student_ID = ...
if vNumber > 0 then
...
else
...
end if;