Gene Wirchenko wrote:
> sztomi_at_seznam.cz (sz Tomi) wrote:
>
> [snip]
>
>
>>SELECT i.date,c.name,c.address FROM invoices AS i INNER JOIN customers
>>AS c ON i.CustomerId=c.CustomerId
>>GO
>>
>>date name address
>>
>>2004-01-01 00:00:00.000 First Company Ltd. Boston
>>2004-01-02 00:00:00.000 First Company Ltd. Boston
>>2004-01-02 00:00:00.000 Second Company Ltd. Washington
>>2004-01-03 00:00:00.000 Second Company Ltd. Boston
>>
>>Is it possible in any of the RDBMS's to make this last query return
>>the following result set?
>>
>>2004-01-01 00:00:00.000 First Company Ltd. New York
>>2004-01-02 00:00:00.000 First Company Ltd. New York
>>2004-01-02 00:00:00.000 Second Company Ltd. Washington
>>2004-01-03 00:00:00.000 First Company Ltd. Boston
>
>
> No, because you do not have enough information. You need to
> associate a date range with the addresses and use that date range with
> the customer id to select the then-current address. To my somewhat
> less than expert eyes, this would involve creating a table of
> addresses keyed to customer id and effective date.
>
> To those more expert, am I on the right track?
Since none of the real experts answered let me confirm that you are
indeed on the right track. :-)
Received on Sat Jul 10 2004 - 01:22:04 CDT
