Question

I’d like to perform a join on a column which contains a value I would like to split on. So if the column contained email addresses I would like to join on the part before the “@” symbol.

I have seen the split function, but I didnt see anywhere I could choose which array element to pick from the result of the split?

So something like:

JOIN ON dbo.split('@',T1.Column)(0)?

Answer 1

I think you’re better off just joining on the substring up to the @ symbol:

SELECT *
FROM Email 
LEFT JOIN EmailName ON Substring(Email.Address, 1, CharIndex('@', Email.Address) - 1) = EmailName.Name

See fiddle here:
http://www.sqlfiddle.com/#!6/5d0f5/8