MS SQL trigger remove all before - sql-server

Question

Need some help...
I have a column whereby the data is shown as -
USEREMAIL:-USERNAME
e.g.
John.smith#test.com:-JSmit
janet.smit#test.co.uk:-JanSmit
peter.parker#test.ca:-PPark
I need a trigger that will automatically remove everything apart from the username when a new entry is added.
So the above examples would just become
JSmit
JanSmit
PPark
Any suggestions would be greatly appreciated.

Answer 1

Here is the syntax to create the described trigger:
Test table:
CREATE TABLE xx(UserName varchar(100))
You will have to expand the trigger to contain all columns.
Trigger syntax:
CREATE TRIGGER xx_trggr
ON xx
INSTEAD OF INSERT
AS
BEGIN
SET NOCOUNT ON;
INSERT INTO xx (UserName)
SELECT stuff(UserName, 1, charindex(':-', UserName) + 1, '')
FROM inserted
END
GO
Inserting data:
INSERT xx(UserName)
values
('John.smith#test.com:-JSmit'),
('janet.smit#test.co.uk:-JanSmit'),
('peter.parker#test.ca:-PPark')
Testing input:
SELECT UserName FROM xx
Result:
UserName
JSmit
JanSmit
PPark
You could make an AFTER trigger instead, but that would require a unique key
Using this table instead:
CREATE TABLE xx(id int identity(1,1), UserName varchar(100))
And this trigger:
CREATE TRIGGER xx_trggr
ON xx
AFTER INSERT
AS
BEGIN
SET NOCOUNT ON;
UPDATE xx
SET [UserName] = stuff(xx.UserName, 1, charindex(':-', xx.UserName) + 1, '')
FROM inserted JOIN xx On inserted.id = xx.id
END
Same result as the other trigger.

Answer 2

You need to create a AFTER INSERT trigger on your table and in your trigger body use something like below to strip down the email part
select right('John.smith#test.com:-JSmit',(LEN('John.smith#test.com:-JSmit') - CHARINDEX('-','John.smith#test.com:-JSmit')))

Answer 3

This will give you username from column
SET columnName= select SUBSTRING( columnName, CHARINDEX('-',columnName)+1 , LEN(columnName))
Use it in trigger
EDIT 1: (If you are worried your email can contain -)
SET columnName= select SUBSTRING( columnName, CHARINDEX(':-',columnName)+2 , LEN(columnName))