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Is a LEFT JOIN with a subquery possible?

I have a list of towns in tblTownData, and a list of people's names in
tblNames. During a year, there are multiple events where more names are
added in tblNames, for a particular town.

1 1 John Doe
1 1 Jane Doe
1 2 Bell E. Dancer
1 2 Frank N. Furter

For each event, I am trying to give feedback to the user as to which towns
have not had a single name added yet. That is, I am trying to generate a
list of towns using a left join on a subquery.

In Access, I can create a query (tblCurrentName sInTown):
SELECT tblNames.TownID
FROM tblNames
WHERE (((tblNames.ELE CTIONID)=1))

then a new query (tblTownData Without Matching Current):
SELECT tblTownData.Mun icipality
FROM tblTownData LEFT JOIN tblCurrentNames InTown ON tblTownData.Tow nID =
tblCurrentNames InTown.TownID
WHERE (((tblCurrentNa mesInTown.TownI D) Is Null));

This will return my list fine.

However, I need to call this query result from the database using a SQL
statement inside an ASP page.

Can you create a LEFT JOIN to the subquery (tblCurrentName sInTown)?
If so, can anyone help with the syntax?
Nov 13 '05 #1
3 22443

Dave wrote:
I have a list of towns in tblTownData, and a list of people's names in
tblNames. During a year, there are multiple events where more names are
added in tblNames, for a particular town.

Did you consider doing something simpler like:

SELECT Municipality FROM tblTownData WHERE TownID NOT IN (SELECT

Of course, if the number of records in tblNames is fairly large the
'NOT IN' syntax becomes inefficient and could explain the route you've

James A. Fortune

Nov 13 '05 #2
Jim's suggestion is excellent. However, if you must use the join, you
can do the following:

SELECT tblTownData.Mun icipality
(SELECT tblNames.TownID
FROM tblNames
WHERE (((tblNames.ELE CTIONID)=1))) AS tblCurrentNames InTown
ON tblTownData.Tow nID =
tblCurrentNames InTown.TownID
WHERE (((tblCurrentNa mesInTown.TownI D) Is Null));

Bill E.
Hollywood, FL

Nov 13 '05 #3
>I have a list of towns in tblTownData, and a list of people's names in
tblNames. During a year, there are multiple events where more names are
added in tblNames, for a particular town.

James and Bill,

Thanks for the feedback. This seemed to work well. I'm next going to load
the database with roughly the same number of records as I would expect over
several events, and determine which way to go.

Thanks for saving my sanity!

Nov 13 '05 #4

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