SQL 2000 - Checksum - How does it work? 1

[MissyEd]

Can anyone point me to a white paper or resource on the internal workings of the checksum function in SQL 2000?

We are considering creating a function externally that replicates this function and can be used to compare rows from a VMS based system against SQL rows without having to compare every column.

Your thought are as always, very welcome.

"There are only two lasting bequests we can hope to give our children; one of these is roots, the other wings" - Hodding Carter

 

[SQLDenis]

here is how I use it

http://sqlservercode.blogspot.com/2006/05/sql-compare-without-price-tag.html

Scroll down to data mismatch, if you have other questions let me know

Denis The SQL Menace
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[MissyEd]

Thanks for the link but the master data we want to compare isnt in SQL. It is in VMS and each file can consist of millions of rows. At the moment, we have a program that uses an odbc connection to reach into sql and find out for example which keys are missing but it is still a serial read operation.

Ideally we want to mod this program to generate a checksum per row in the VMS file, then compare it against the checksum generated by SQL, if they are different, the row will be marked for a push through to SQL.

For us to test this approach, I need to understand how the checksum works, if it is an industry standard for example, I can inform the VMS team so they can replicate it.

"There are only two lasting bequests we can hope to give our children; one of these is roots, the other wings" - Hodding Carter

 

[SQLDenis]

here you go:

http://www.rampant-books.com/t_super_sql_65_crc32_checksum_algorithm.htm

Denis The SQL Menace
--------------------
SQL Server Code,Tips and Tricks, Performance Tuning
Google Interview Questions

 

[MissyEd]

Thats great, thank you very much

"There are only two lasting bequests we can hope to give our children; one of these is roots, the other wings" - Hodding Carter