Posted by Erland Sommarskog on 07/19/07 15:32

(anilkmakhija@gmail.com) writes:
> I need to store 256 bit hash (SHA-2 alogrithmn) in one of the table's
> primary key. I would prefer to use numeric data type rather varchar
> etc.
>
> * Decimal datatype range is -10^38 +1 to 10^38 -1. I can split my 256
> bit hash into two decimal(38, 0) type columns as composite key
> * I can store the hash as varbinary. I never used it and don't have
> much understanding in terms of query writing complexities and dealing
> it through ADO (data type etc.)
>
> It would be heavy OLTP type of systems with hash based primary key
> used in joins for data retrieval as well.

I don't see what purpose the kludge with decimal should serve. Would you
not be left with a lot of code that converts forth and back?

Isn't the hash always always 256 bits? In such case would not binary(32)
be a better choice than varbinary.

Using a binary as key should be relatively straight forward. Of course,
there is some cost due to the size of the key, but that would not be any
better with decimal.


--
Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se

Books Online for SQL Server 2005 at
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