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Help with a tough query

Help with a tough query

2004-03-15       - By Brent Baisley

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Reply:     1     2     3     4     5     6     7     8  

I didn 't think this was too hard when I first created it, but now that
I 'm loading test data it 's not working as expected.

The core of the query is three tables: Event, Contact, and Regarding.
There can be zero or more Contacts for each event and zero or more
"Regardings " for each event. There are also 7 left joins I do to get
other linked data, but that 's working fine.

So, the question is, how do I get a list of events with possible
multiple contacts and multiple regardings?

The problem I run into with my current query is that it fails when
there are no contacts or regardings for an event. Is this possible in a
single query? Here is a short version of my current query.
SELECT DISTINCT EventID, Contact.Name, Regarding.Name
FROM Events, Contacts, Regarding
WHERE Events.EventID=Contacts.EventID AND
Events.EventID=Regadings.EventID

It is possible that I can make the Contacts database a one to many
relation since 99% of the time there will be an associated contact
record. I can make a "dummy " record for the 1% exception, but it feels
"unclean ". But if it makes it easier, so be it.
Right now I am running 4.0, but I 'm not tied to any version yet.

Thanks
--
Brent Baisley
Systems Architect
Landover Associates, Inc.
Search & Advisory Services for Advanced Technology Environments
p: 212.759.6400/800.759.0577


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