hash options

Hello,

I'm working on a data warehouse dimensionalization process where I need to hash a text string to use as the key.
I've implemented with MD5. It works fine, the problem I have is the size of the md5 (32 bytes) is often longer than the original string - thus not accomplishing what I want - space savings.

Does anybody have alternative hash function recommendations?
I looked at the options I knew of
select length(encode('ar=514','hex')); -- 12
select length(decode('ar=514','base64')); -- 24
select length(DIGEST('ar=514', 'md5')) -- 16bytes
select length(DIGEST('ar=514', 'sha1')) -- 20bytes

function is currently written in pg/plsql, but I'm considering switching to python for broader library choice.

Source data is delimited list of name/value pairs. Length range from 0-2500 bytes.
ar=514,cc=CA,ci=Montreal,cn=North+America,co=Sympatico,cs=Canada,nt=Xdsl,rc=QC,rs=Quebec,tp=High,tz=GMT%2D5

Thanks in advance
Doug Little

Sr. Data Warehouse Architect | Business Intelligence Architecture | Orbitz Worldwide
Douglas(dot)Little(at)orbitz(dot)com<mailto:Douglas(dot)Little(at)orbitz(dot)com>
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