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Archives of the TeradataForum
Message Posted: Sun, 18 Aug 2003 @ 02:40:05 GMT
| Subj: | | Re: Assigning destination tags to CDRs |
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| From: | | Burton, Bruce |
Dieter,
I would say #2 or concatenating a '0000' and '9999' to get start and end ranges (called line ranges in the telco world) and then
using a between (where called_no between trim(prefix||'0000') and trim(prefix||'9999')). I'm definitely not a SQL efficiency guru so
I have no clue if the above would be faster than your #2. I assume loading the prefix table with the line ranges and then doing the
join would be pretty quick since this is how many of the billing engines process call records (use the line range to calc the
distance of the call for pricing, etc.). The above assumes your 'prefix' is the npa/nxx (1st 6 digits of the phone #) but I guess
you could create npa-000-0000 and npa-999-9999 table rows to do the same if you only have the npa. A case test on the prefix could
dictate when line range to use on the join...but this seems to get back to your #2 solution.
It gets a little trickier when you get into international traffic and country and city codes...which may not always line up on the
record consistently (sometimes the record is missing the city code, etc.)...but that's a whole different story.
Thanks,
Bruce
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