RE: Compare the text in a string (Re-post)

SSC Guru

Points: 186127

June 26, 2012 at 3:29 am

Jeff Moden (6/25/2012)
ChrisM@Work (6/25/2012)
This works quite nicely too:
SELECT
EmployeeID,
Email,
DomainLHS = SUBSTRING(Email, x.PosStart,x.PosEnd-x.PosStart),
DomainRHS = SUBSTRING(Email, y.PosStart,y.PosEnd-y.PosStart)
FROM @t
CROSS APPLY (
SELECT PosStart = 1+CHARINDEX('@',EMAIL,1),
PosEnd = NULLIF(CHARINDEX('.',EMAIL,CHARINDEX('@',EMAIL,1)),0)
) x
CROSS APPLY (
SELECT PosStart = NULLIF(1+CHARINDEX('@',EMAIL,x.PosEnd),1),
PosEnd = NULLIF(CHARINDEX('.',EMAIL,CHARINDEX('@',EMAIL,x.PosEnd)),0)
) y
Absolutely awesome, Chris. "Cascading Cross Applys" (cCA for short! :-D). Looks like it might beat the tar out of cascading CTE's of a similar nature. To be honest, I didn't know such a thing was possible because I didn't even consider that one CA might be able to use the output of another. This crazy Monday has turned into something good after all!
You should write a "Spackle" article on it, Chris.

Gosh :blush: thanks Jeff!

I might have to do just that 😉

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