Retrieve initial table in AFTER INSERT trigger SQL - sql

I use this code to check if an element of the new entry is equal to an element of previously inserted data.
CREATE TRIGGER trig1 ON Table1
AFTER INSERT
AS
DECLARE trigcursor CURSOR FOR
SELECT Name FROM INSERTED
DECLARE #Name1 varchar(80)
OPEN trigcursor;
FETCH NEXT FROM trigcursor INTO #Name1
WHILE ##FETCH_STATUS = 0
BEGIN
IF EXISTS(SELECT * FROM Table1 WHERE Name= #Name1)
BEGIN
...
END
FETCH NEXT FROM trigcursor INTO #Name1
END
The problem is that for some reason the new entry exists also in the table Table1, not only in INSERTED. So the condition is always true. Can you help me why this happens? Is there a way to retrieve only the initial table without the new entry in it? Thanks!

Your trigger is AFTER INSERT on table Table1. It should be BEFORE INSERT if you expect not to find the record in the table.
Alternative: use INSTEAD OF INSERT trigger.
OR
Add another column that accepts null. Make it a number column so that it will be fast. Do not insert any value in it on the insert. Then, in the AFTER INSERT TRIGGER, the rows that have that column empty are the new ones. The ones that have the column filled with something are the old ones.
Then update empty columns with value.
eg: add column mark
After insert, look for the name:
SELECT * FROM Table1 WHERE Name= #Name1 and mark is not null
Once you found out whether or not it existed before, update everything with something:
update table1 set mark = 1 where mark is null

Related

How to Retrieve the Identity column value in an insert trigger SQL Server

I have two tables that are identical except one has an identity column and the other doesn't. Instead the second table uses the value of the identity column from the first table. I thought I would insert into the second table as a trigger when a record is inserted into the first table. I cannot seem to get syntax right.
Null is being returned from the identity column #EDVisitId.
ALTER TRIGGER [dbo].[trgInserterrEDVisitOriginal] ON [dbo].[errEDVisit]
AFTER INSERT
AS
--Name: Bob Avallone
--Date: 6-15-2017
--
-- The purpose of this trigger is to insert a record into errEDVisitOriginal
-- whenever a new errEDVisit is inserted.
--XXXXXXXXXX
declare #EDVisitId int
declare #SubmissionControlID INT
Select #EDVisitId = EDVisitID from inserted
SELECT #SubmissionControlID = SubmissionControlID from Inserted
Begin
Insert Into errEDVisitOriginal (EDVisitId, SubmissionControlID)
VALUES (#EDVisitId, #SubmissionControlID )
End
Thanks for all the suggestions. I abandoned the idea of a trigger. Instead I simply insert the new records from the first table into the second one. See below.
Insert errEDVisitOriginal(EdVisitId, SubmissionControlID)
Select EdVisitId, SubmissionControlID
from errEDVisit where SubmissionControlID = #SubmissionControlID
you just need scope_identity()
Select #EDVisitId = scope_identity()
You can use SCOPE_IDENTITY to get the last inserted id from the first table put it into a variable then insert into the second table.
https://learn.microsoft.com/en-us/sql/t-sql/functions/scope-identity-transact-sql
Though the decision to duplicate information intentionally is dubious, you are vastly over-thinking the code. Just:
if exists (select * from inserted)
insert dbo.errEDVisitOriginal (EDVisitId, SubmissionControlID)
select EDVisitId, SubmissionControlID from inserted;

Trigger to delete prior duplicate records in the table

I need to write a trigger based on the following condition
Before inserting a record in the table, I need to compare the value of one column to the existing records, and if records found then I need to delete those records having same column value in the already existing records, and then need to insert that new record.
Please let me know how to achieve this.
Thanks
CREATE TRIGGER [dbo].[CustomInsert_Trigger] ON [dbo].[Realtimebookingcount]
INSTEAD OF INSERT AS
BEGIN
DECLARE #Flag INT
SELECT #Flag = Booking_NUM FROM inserted
IF (SELECT COUNT(1) FROM Realtimebookingcount
WHERE Booking_NUM = #Flag) > 0
BEGIN
DELETE FROM Realtimebookingcount
WHERE Realtimebookingcount.Booking_NUM = #Flag
END
INSERT INTO Realtimebookingcount
SELECT * FROM inserted
END

After insert not working

all id columns has auto_increment
In my trigger:
ALTER trigger [dbo].[mytrig]
on [dbo].[requests]
after INSERT, UPDATE
as
begin
declare #MyId1 int
set #MyId1 = (select Id from inserted)
declare #MyId2 int
declare #MyId3 int
if (select column1 from inserted) = 1
begin
insert into [dbo].[contracts] select column1,column2,column3 .... from inserted
set #MyId2 = SCOPE_IDENTITY()
insert into [dbo].[History] select column1,column2,column3 .... from inserted
set #MyId3 = SCOPE_IDENTITY()
insert into [dbo].[contracts_depts](Id_Contract ,column5) select #MyId2,column6 from request_depts where Id_request=#MyId1
insert into [dbo].[History_depts] (Id_InHistory,column5) select #MyId3,column6 from request_depts where Id_request=#MyId1
end
end
#MyId1 returns value only after update but not after insert. Do I have to use scope_identity() or something ?
Your main issue is: you're assuming the triggers is called once per row - that is NOT the case!
The trigger is called once per statement, and if your statement affects multiple rows, the Inserted pseudo table will contain multiple rows - so your statement here
set #MyId1 = (select Id from inserted)
really isn't going to work - it will select one arbitrary row (out of however many there are).
You'll need to rewrite your trigger to take this fact into account! Assume that Inserted contains 100 rows - how do you want to deal with that? What are you trying to achieve? Triggers don't return values - they will record into an audit table, or update other rows, or something like that ....

How to write trigger to insert and update another table

I want to write trigger. When there is an entry in table1, table2 should get inserted with same values. And in some field in table1 is updated then respective field must get updated in table2. How can I know whether value is inserted or updated?
I am using inserted to insert value.
Please guide me.
Here is how you will know whether a value is inserted or updated in a trigger like this:
on INSERT, the inserted dynamic table is populated with the new values
on UPDATE, the inserted dynamic table is populated with the new values of the records that were updated, and the deleted dynamic table is poulated with the old values of the records that were updated
So basically, if the deleted table contains the id (assuming you have an id column) as in the inserted table, you can be assured that it was an UPDATE that caused the trigger. If the deleted table is empty, conversely, it was an INSERT.
use this trigger to solve your problem..
create TRIGGER [dbo].[insert_Assets_Tran]
ON [dbo].[AssetMaster]
AFTER INSERT , UPDATE
AS BEGIN
DECLARE #isnum TINYINT;
SELECT #isnum = COUNT(*) FROM inserted;
IF (#isnum = 1)
INSERT INTO AssetTransaction
select [AssetId],[Brandname],[SrNo],[Modelno],[Processor],[Ram],[Hdd],[Display],[Os],[Office],[Purchasedt]
,[Expirydt],[Vendor],[VendorAMC],[Typename],[LocationName],[Empid],[CreatedBy],[CreatedOn],[ModifiedBy]
,[ModifiedOn],[Remark],[AssetStatus],[Category],[Oylstartdt],[Oylenddt],[Configuration]
,[AStatus],[Tassign]
FROM inserted;
ELSE
RAISERROR('some fields not supplied', 16, 1)
WITH SETERROR;
END

INSERT trigger to update a field that is NOT NULL in the same table

I have a situation where I need to merge two product tables into one and need to keep both id fields. The Id field is the pk and an identity column. On insert I want to update the prodId to match the Id of the newly inserted row. This is what I have but I get an error saying that I cannot insert null into ProductId. What am I doing wrong?
ALTER TRIGGER SyncId
ON Product
FOR INSERT
AS
BEGIN
DECLARE #ID INT
SET #ID = (SELECT ID FROM Inserted)
UPDATE Product SET
ProdId = #ID
WHERE
Id = #ID
END
You could create an INSTEAD OF trigger for the INSERT. You would then have to recreate the actual INSERT logic. You might need a view of the table for the trigger to sit on though... I don't recall if an INSERT within the trigger will work or not and can't test it right now.
Also, your trigger as written will only work if a single row is being updated. You should always write your triggers to be able to handle multiple rows in the INSERTED and DELETED tables.