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Data type for hash keys

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Joined: 1 year ago


in our DV2 implementation we are using zOS DB2 V12 as the RDBMS.

Is there any reason why not to use a binary data type to store the hash keys (HKs)?

We are using MD5 as the hash function.

We were planning on using a CHAR(32) data type to store the HKs in order to have a readable representation of the HK,

but the architect in the project suggested we would have "significant" spaces savings including savings in I/Os due to the smaller size of the binary data type that would contain the identical information.

Any thought on this?

I tried looking for other threads in this topic but couldn't find anything. So if this has been discussed before,

my apologies in advance and please simply point me to the thread or the search terms to use 😉 !

Regards from Bavaria Germany,


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