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Trigger: How does the inserted table work? How to access its rows?

I have the following table

Data --Table name
ID -- Identity column
PCode -- Postal Code

I created the following trigger:

CREATE TRIGGER Trig
ON Data
FOR INSERT
AS
BEGIN 

    Select * from inserted

END

And inserted the following values

INSERT INTO Data VALUES (125)
INSERT INTO Data VALUES (126)
INSERT INTO Data VALUES (127)

It shows this:

enter image description here

But I was expecting something like this:

  • After the 1st insertion, the trigger is executed -> one row is shown in the inserted table.
  • After the 2nd insertion, the trigger is executed -> two rows are shown in the inserted table.
  • After the 3rd insertion, the trigger is executed -> three rows are shown in the inserted table.

According to msdn.microsoft all the rows inserted are in this table.


How can I access the inserted table so that I can see all the expected rows and not separately?

like image 495
Jazz Avatar asked Nov 13 '16 16:11

Jazz


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How do I get the insert row in a trigger?

To create a trigger, we need to change the delimiter. Inserting the row into Table1 activates the trigger and inserts the records into Table2. To insert record in Table1. To check if the records are inserted in both tables or not.

What is inserted table in trigger?

The inserted table stores copies of the new or changed rows after an INSERT or UPDATE statement. During the execution of an INSERT or UPDATE statement, the new or changed rows in the trigger table are copied to the inserted table.

How do we use inserted and deleted tables outside of trigger?

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2 Answers

You can not. From the Use the inserted and deleted Tables article on microsoft.com, you can read:

The inserted table stores copies of the affected rows during INSERT and UPDATE statements.

That means that the inserted table will only contain rows for the current INSERT or UPDATE statement.

If you do want to see all rows for several such INSERT or UPDATE statements, you will have to store these rows in a table you created yourself.

like image 126
TT. Avatar answered Nov 04 '22 19:11

TT.


There are 2 table available in a trigger, the inserted and the deleted. Each update on table XXX is actually a delete row X from XXX then an insert of row X in table XXX. So the inserted inside the trigger is a copy of what got inserted. You can do a lot with a trigger, but triggers are dangerous.

For example, on a performance gig, I found a huge SP being run by a trigger, we dropped it and the database came back online. Or another example, if you do a trigger wrong to audit logins, you can down the server.

like image 45
Duane Lawrence Avatar answered Nov 04 '22 21:11

Duane Lawrence