Issue with Trigger - sql-server

Question

I am working with an insert trigger and work fine. I am creating an insert trigger and take a backup in tblHist table.
I have two tables:
tblUser - creating this table for insert,update and delete purpose
tblHist - creating this table for store a record for history purpose
tblUser table design:
tblHist table design:
Then I create an insert and update trigger:
ALTER TRIGGER [dbo].[trgr_tblUser_AFTERINSERT]
ON [dbo].[tblUser]
AFTER INSERT, UPDATE
--,DELETE
AS
BEGIN
DECLARE #userid int, #username varchar(50),
#useraddress varchar(50), #countryname varchar(5),
#statename varchar(50), #cityname varchar(50);
BEGIN
SELECT
#userid = u.userid, #username = u.username,
#useraddress = u.useraddress,
#countryname = u.countryname,
#statename = u.statename, #cityname = u.cityname
FROM tblUser u;
INSERT INTO tblHist (userid, username, useraddress, countryname, statename, cityname)
VALUES (#userid, #username, #useraddress, #countryname, #statename, #cityname);
PRINT 'AFTER INSERT update trigger fired.'
END
END
When I insert a record into the tblUser table, then it inserts a record into the tblHist table - this is working fine.
See below
Then I update a record then insert a history in tblHist table working fine.
but issue is when I add a code for delete a record functionality in trgr_tblUser_AFTERINSERT then delete functionality not work
And when I create a delete trigger separately then work fine
See below
ALTER TRIGGER [dbo].[trgr_tblUser_AFTERDELETE]
ON [dbo].[tblUser]
FOR DELETE
AS
BEGIN
DECLARE #userid int, #username varchar(50),
#useraddress varchar(50), #countryname varchar(5),
#statename varchar(50), #cityname varchar(50);
SELECT
#userid = u.userid, #username = u.username,
#useraddress = u.useraddress, #countryname = u.countryname,
#statename = u.statename, #cityname = u.cityname
FROM deleted u;
INSERT INTO tblHist (userid, username, useraddress, countryname, statename, cityname)
VALUES (#userid, #username, #useraddress, #countryname, #statename, #cityname);
PRINT 'AFTER DELETE trigger fired.'
END
I want to add insert, update, delete trigger functionality In one trigger but not work.
What I am trying:
exist select 1 --- but not work
which place I am doing wrong need help

Answer 1

I highly doubt that your first trigger will work properly .... you're just selecting an arbitrary rows from your tblUser table - not even one that's necessarily just been inserted or updated ....
I would strongly recommend these changes:
creating a separate trigger for each operation - that makes the trigger simpler, since you don't need to first figure out what you're dealing with....
add a ModifiedOn DATETIME2(3) column to your tblHist to record the date & time stamp when the change occurred
also possibly add an Operation column to your tblHist - so that you can understand what operation (insert, update, delete) caused this entry in the history table
properly handle the Inserted and Deleted pseudo tables in your trigger code taking into account they can (and will!) contain multiple rows - handle them in a proper, set-based fashion
drop the PRINT - makes no sense inside a trigger....
Code would be something like:
CREATE OR ALTER TRIGGER dbo.trgr_tblUser_AfterInsert
ON dbo.tblUser
AFTER INSERT
AS
BEGIN
-- do an "INSERT INTO" ...
INSERT INTO tblHist (ModifiedOn, userid, username, useraddress, countryname, statename, cityname)
-- based on the "Inserted" pseudo table, and use proper set-based approach
SELECT
SYSDATETIME(),
i.userid, i.username, i.useraddress, i.countryname, i.statename, i.cityname
FROM
Inserted i;
END
END
and
CREATE OR ALTER TRIGGER dbo.trgr_tblUser_AfterDelete
ON dbo.tblUser
AFTER DELETE
AS
BEGIN
INSERT INTO tblHist (ModifiedOn, userid, username, useraddress, countryname, statename, cityname)
SELECT
SYSDATETIME(),
d.userid, d.username, d.useraddress, d.countryname, d.statename, d.cityname
FROM
Deleted d;
END
END

Answer 2

If you want to check whether it was an insert, update or delete, you have to examine the row count of the inserted and deleted pseudotables - for an insert, records are only present in inserted, for delete they are only present in deleted. An update has both so you can tell the old values (deleted) and the new (inserted)
Make your life easy; put twice as many columns in your hist (should be called UserHist, no?) table as your user table, and make them e.g. old_username, new_username.. an insert the result of a full outer join between the inserted and deleted tables, this way you can tell if it was an insert, update or delete and particularly for an insert, what changed to what
Alternatively, use something like
IF EXISTS(SELECT null FROM inserted)
IF EXISTS(SELECT null FROM deleted)
--it was an update
ELSE
--it was an insert
END;
ELSE
--it was a delete
END;
Or, make 3 separate triggers
Final point of note, you're doing these queries wrong - you're declaring a bunch of variables (that can only hold a single value)and selecting the values from inserted/deleted into them but those pseudotables can have more than one row, if the query affected multiple rows (such as DELETE FROM user WHERE name = 'John')
You should be doing your operations in a bunch-of-rows way, not a "single row" way:
INSERT INTO tblHist
SELECT * FROM inserted
This can insert multiple rows into hist, and this is the way you should always think about doing things in SQLServer.. Even if you only ever insert one row and your inserted pseudotable has one row, you must get into the habit of treating it as "a collection of rows with one entry" so that any code you write won't fall apart when one day it becomes "a collection of rows with multiple entries"
Note in one of your attempts you did not select from inserted, you selected from the users table - this is wrong:
Of course, an AFTER delete trigger will insert nothing if you just deleted the only row from tblusers, but you shouldn't be using tblusers anyway