I did something similar.  I made a persisted calculated field in the staging table that held the hash value.  Then the CPU for hash calculation would get hidden by the...

So I had a weird setup. 

• Client needed to migrate from a legacy server that had 4 instances, where instance 1 was the default instance on port 1433.  

andrew_c_worth@yahoo.co.uk (9/30/2015)

Dealing with the problem when it comes may well be a case of "Not my Problem", but someone will have to fix it. Software often ends up being used...

If you are doing single email look ups, I don't think anyone doubts the hash lookup can give you a reduction in logical I/O for slight increase in disk space,...

You need to be very careful with your data types. If you have a variable that is varchar and a variable that is nvarchar, they make different hashes. ...

I guess it is possible that I misunderstood what SQL server is doing with the keyhash values stored in the index pages. It is certainly hashing the strings and...

I managed a database with > 10 Million...

It is not hard to create email addresses where Checksums overlap.

if checksum('ks@gmail.com') = checksum('nc@gmail.com')

print 'Checksum function is weak'

If you really want to do something like this, I'd recommend hashbytes:

if convert(bigint,hashbytes('md5','ks@gmail.com'))...

I have a similar challenge.

I have 40 servers.

Each server has a [dbadb] database.

Each database has a view named v_DatabaseFiles that shows information on the database files & mountpoint...