I want to launch a trigger if a user try to replace current date with a future date.But subquery might not allowed in trigger. How can i solve this issue? Any suggestion....
CREATE OR REPLACE TRIGGER check_join_date
BEFORE UPDATE OF join_date ON DOCTOR
FOR EACH ROW
WHEN (NEW.join_date > (SELECT CURRENT_DATE+1 FROM DUAL) )
BEGIN
RAISE_APPLICATION_ERROR(-20509,'Do not Enter Future Date..');
END check_join_date;
/
I am getting this error after running this code in Oracle.
ORA-02251: subquery not allowed here
test this
CREATE OR REPLACE TRIGGER check_join_date
BEFORE UPDATE OF join_date ON DOCTOR
FOR EACH ROW
WHEN (NEW.join_date > CURRENT_DATE+1)
BEGIN
RAISE_APPLICATION_ERROR(-20509,'Do not Enter Future Date..');
END check_join_date;
/
Related
For an assignment I need to write an Oracle SQL trigger that prevents the StdBalance column in the STUDENT table from exceeding 500. Normally I would just use a check constraint to enforce this however I am being forced to write a trigger for it. As expected Oracle is throwing a mutating error due to me using SELECT in an update trigger and will not let me update the StdBalance value with anything. Does anyone have any idea how I could work around this? Here is the code for the trigger.
CREATE OR REPLACE TRIGGER Balance_Trigger
BEFORE UPDATE ON STUDENT
FOR EACH ROW
DECLARE
Current_Balance NUMBER;
BEGIN
SELECT :new.StdBalance
INTO Current_Balance
FROM STUDENT
WHERE :new.stdID = StdID;
IF Current_Balance > 500
THEN Raise_Application_error(-20007, 'You cannot exceed an unpaid balance of $500');
end if;
end;
/
show error;
Just use :
Current_Balance := :new.StdBalance;
Instead of
SELECT :new.StdBalance
INTO Current_Balance
FROM STUDENT
WHERE :new.stdID = StdID;
to suppress the mutating error.
P.S. Even if such assignments are used in these cases, as David Faber warned, there's no need to return a value for Current_Balance, :new.StdBalance may be used directly in comparison for IF :new.StdBalance > 500 ....
I do not know how to compare 2 Dates in a trigger (one in the table and the current Date)
Here is my draft of the trigger:
CREATE trigger check_update
BEFORE DELETE ON customer_contract
For each row
Begin
If(date_to_cancel_contract > (<date>))
Signal sqlstate ‘45000’
Set message_text = ‘Error, not allowed to cancel contract.’
END IF
What’s wrong? How can I fix the problem?
The condition should be (provided it is SQL Server)
If(date_to_cancel_contract > dateadd(day,datediff(day,0,getdate()),0))
I wrote this trigger to update a certain column. The trigger I wrote is this:
CREATE TRIGGER updateotMark
BEFORE UPDATE
ON sBookBorrow
FOR EACH ROW
WHEN(SYSDATE-to_date(etime)>15)
BEGIN
UPDATE otMark = 1;
END;
/
This is the first time I use trigger, so I have no idea what went wrong. Any ideas? Thanks everyone for your answer.
UPDATE: This is what I got in the console. What did I do wrong?
UPDATE2:Now it has a error message:ERROR at line 5:
ORA-04076: invalid NEW or OLD specification
What is the data type of "etime"?
If date, you don't need to use "TO_DATE" function. ex.(SYSDATE - etime > 15)
If VARCHAR2, you need to put the format. ex. TO_DATE(etime,'YYYYMMDD')
However, use SHOW in SQLPlus will give you more information about error.
SHOW ERROR TRIGGER updateotMark;
Let try this.
CREATE OR REPLACE TRIGGER updateotMark
BEFORE UPDATE
ON sBookBorrow
FOR EACH ROW
WHEN (SYSDATE - NEW.etime > 15)
BEGIN
:NEW.otmark := 1;
END;
Just update the :new value
CREATE TRIGGER updateotMark
BEFORE UPDATE
ON sBookBorrow
FOR EACH ROW
WHEN(SYSDATE-to_date(etime)>15)
BEGIN
:new.otmark = 1;
END;
Hello guys I'm a bit of a noob when it comes to triggers so I'm just looking for some advice on how to do the follow trigger.
I have created a trigger that will throw an error message if someone was to delete a record during office hours however I would like to create another trigger that uses SYSDATE will not delete records from say today and future dates.
I was thinking of maybe using >=SYSDATE but I'm not sure if that is a valid sql statement.
CREATE OR REPLACE TRIGGER records_delete
BEFORE DELETE
ON RECORDS FOR EACH ROW
BEGIN
IF TO_CHAR(SYSDATE, 'HH24MI') NOT >= sysdat
RAISE_APPLICATION_ERROR(-20669, 'You can not delete current or future records');
END IF;
END records_delete;
Thanks, leprejohn
The problem here is that you're not referencing any of the fields of the table that you're deleting from.
If your table had a column called record_date then you could rewrite this as:
CREATE OR REPLACE TRIGGER records_delete
BEFORE DELETE
ON RECORDS FOR EACH ROW
BEGIN
IF (:old.record_date >= SYSDATE) THEN
RAISE_APPLICATION_ERROR(-20669, 'You can not delete current or future records');
END IF;
END records_delete;
The syntax :old. and :new. are how you reference the columns of the current record being acted upon by the trigger, with :old. being the prefix for inspecting the values before the trigger acts on it and :new. being for values after the trigger is done. This syntax allows you to see the values before/after the trigger updates the data, which in your case doesn't matter since you're deleting records.
If you want to disregard the hours, mins, seconds of the date fields, use this in the IF statement
trunc(:old.record_date) >= trunc(SYSDATE)
If record_date is actually stored as a string instead of a date, you would convert it to a date before comparison:
to_date(:old.record_date, 'DDMMYYYY') >= trunc(SYSDATE)
Update the format mask 'DDMMYYYY" to the format your date is actually stored in. Check the Oracle documentation for description of to_date and date format models.
Give this a shot and see if it works.
I have account table as this--
create table account
(
acct_id int,
cust_id int,
cust_name varchar(20)
)
insert into account values(1,20,'Mark');
insert into account values(2,23,'Tom');
insert into account values(3,24,'Jim');
I want to create a trigger which will ensure that no records can be inserted or update in account table having acct_id as 2 and cust_id as 23.
My code is --
create trigger tri_account
before insert or update
on account
for each row
begin
IF (:new.acct_id == 2 and :new.cust_id == 23) THEN
DBMS_OUTPUT.PUT_LINE('No insertion with id 2 and 23.');
rollback;
END IF;
end;
so this trigger is created , but with compilation error.
now when I insert any record with acct_id as 2 and cust_id as 23,it doesent allow.
But I get an error saying
ORA-04098: trigger 'OPS$0924769.TRI_ACCOUNT' is invalid and failed re-validation
I don't understand this.I also want to show a message that dis insertion is not possible.
please Help...
The equality operator in Oracle is =, not ==.
You cannot commit or rollback in a trigger. You can throw an exception which causes the triggering statement to fail and to be rolled back (though the existing transaction will not necessarily be rolled back).
It does not appear that this trigger compiled successfully when you created it. If you are using SQL*Plus, you can type show errors after creating a PL/SQL object to see the compilation errors.
You should never write code that depends on the caller being able to see the output from DBMS_OUTPUT. Most applications will not so most applications would have no idea that the DML operation failed if your trigger simply tries to write to the DBMS_OUTPUT buffer.
Putting those items together, you can write something like
create trigger tri_account
before insert or update
on account
for each row
begin
IF (:new.acct_id = 2 and :new.cust_id = 23) THEN
raise_application_error( -20001, 'No insertion with id 2 and 23.');
END IF;
end;
A trigger is more flexible, but you can also accomplish this through the use of a CHECK CONSTRAINT:
ALTER TABLE account ADD CONSTRAINT check_account CHECK ( acct_id != 2 OR cust_id != 23 )
ENABLE NONVALIDATE;
The NONVALIDATE clause will ensure that the check constraint does not attempt to validate existing data, though it will validate all future data.
Hope this helps.
IF (:new.acct_id = 2 and :new.cust_id = 23) THEN
must be OR, not and.
While using conditional checks you don't need to use colons (:). This will always cause errors.
Note: Exclude the colon only in cases where condition checking is performed.