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Archives of the TeradataForum
Message Posted: Wed, 24 May 2000 @ 15:05:19 GMT
| Subj: | | Re: Surrogate keys |
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| From: | | Jim Downey |
I don't know if this will help but we use a process where we compare the new data to the old data. If the new data is represented
in the old data, we inherit the surrogate key. If the new data is not represented (and it needs a new key) then we rank the data
using the RANK function. This gives each row a number from 1 to n. We then take max(old data) and add it to the new data. For
example if our old data had keys from 1 to 1000 and the new data had ranked from 1 to 20, when we merge the new data with the old
then we add the max (1000) to each rank giving us new values from 1001 to 1020.
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