I want to know if DBMS_JOB can be used over Trigger.
My requirement is that I want the job to run when Table1 is inserted or updated. I want to know that if I schedule the job every 1 minute to pick the updated/inserted row based on date whether it will put any load on my DB(though the update or insert will not happen frequently). I am using Oracle 11g.
Thanks
The solution is to put trigger that insert data in another table named EVT_Table1 (when you have update or insert) and than let your job execute action on the EVT_Table1.
Related
I'm having a little trouble with understanding functions and triggers in sql. I didn't post the code of procedure chkInsertAritcle but let's say it returns NEW if it managed to make change and NULL if it didn't.
So my question is about the trigger. If I put AFTER INSERT does that means that it will complete INSERT without depending on the return value? And what
happens with the rest of the rows?
Next question is if I put BEFORE INSERT, in what order does code runs?
Thanks!
CREATE TRIGGER ArticleIns
AFTER INSERT ON ListOfArticles
FOR EACH ROW
EXECUTE PROCEDURE chkInsertArticle();
First all BEFORE triggers run in alphabetical order, then the operation is performed, then all AFTER triggers run in alphabetical order.
Each operation sees the result of the previous one as input, and if any trigger returns NULL, processing for that row stops. So if a BEFORE trigger returns NULL, the DML operation won't take place.
This happens independently for each row affected by the triggering DML statement.
So if the trigger runs before insert, then the code runs before the data is inserted into the row and constraints are checked. So for example you might want to add a timestamp before the data is committed to the database,
If it runs after then the data is already present in the table and all constraints have been checked. This is usually where you want to trigger another process based on the row data, maybe update another table, send an e-mail etc.
In your example, the data will be in the database before your procedure runs. So if your procedure modifies the row data, it needs to be in the database.
I want to write a trigger or function which runs automatically and delete the data which are 5 days old . I have a data column in the table which stores the current date. The program will run automatically and delete such data.
I use sql server 2008
Better create a job that runs every night to delete the old data.
Trigger is not a good solution for this case, because every INSERT or UPDATE will invoke the trigger, slowing you down.
Looking for ideas on how to write a trigger that will delete a record when a condition is met.
I have some records being written to a SQL Server 2008 database table. These records that are being written are not important and I would like to see them removed. There are two columns that will have unique information when these records are written and I would like a trigger to remove them as soon as they are written.
I could run a daily job to delete all records that equal X and Y but my thought why not delete the records as they are written.
What would this kind of trigger look like?
If you are not able to change that at any app layer you can use an INSTEAD OF INSERT trigger and those rows will not even be inserted at all.
It will save the database from both inserting and deleting.
The database I am using already has a 2 triggers on part number table (on insert and on update). Insert trigger updates creation date, and update trigger updates modification date.
I have to add 3 more triggers to log updates to this table (on insert, on update and on delete)
In what order they will be executed? Before existing trigger or after? Can I control that?
sp_settriggerorder will allow you to set first or last trigger.
If you have more than two and the order matters, combine them into one trigger and split the functionality over the stored procedures.
If I have a statement
that updates multiple rows, only the trigger will fire only on the first or last row that is being updated (not sure which one). I need to make a trigger that fires for ALL the records that are being updated into a particular table
Assuming SQL Server, A trigger only fires once per update, regardless of the number of rows that are updated. If you need to carry out some additional logic based on updates to multiple rows you can access the changed records by looking at the INSERTED and DELETED logical tables that are accessible in the context of a trigger.
You have not specified the database .....
In Oracle a trigger can be defined to fire for individual rows and based on the type of transaction:
CREATE OR REPLACE TRIGGER BIUDR_MY_TABLE
BEFORE INSERT OR UPDATE OR DELETE
ON MY_TABLE
REFERENCING NEW AS NEW OLD AS OLD
FOR EACH ROW
DECLARE
pk PLS_INTEGER;
BEGIN
etc ....
You just need to indicate if your trigger needs to be executed "FOR EACH ROW" or "FOR EACH STATEMENT". Adding one of these two clauses in the trigger definition will tell the DBMS when to execute the trigger (most, but not all, DBMSs support it). If you don't indicate this clause then the DBMS uses the default option which in your case seems to be the FOR EACH STATEMENT option, and that's why your trigger only fires one for each update sentence, regardless of how many rows you are updating