You can use query below:
DECLARE @Email VARCHAR(50) = 'info@ercanopak.com'
SELECT SUBSTRING(@Email, 1, CHARINDEX('@', @Email) - 1) AS [User Name],
SUBSTRING(@Email, CHARINDEX('@', @Email) + 1, LEN(@Email)) AS [Domain Name]
User Name Domain Name
----------- -------------
info ercanopak.com
Related posts:
Capitalize words in SQL (Display data first letter uppercase rest lowercase)
How to find the first missing value in a series in MS SQL
How to hide letters with asterisks except first letter in SQL
Search text in all tables in SQL Server
Change Default Value for "Select Top n" and "Edit Top n" Rows in SQL Server Studio