Hello Gurus
Aside from being a 'New User' and an engineer my problem(s) involves
Geocoding using two fields and the Combine By Columns command.

I have several tables with data relating to roads (eg. DailyTraffic,
Accidents1999, etc).  Each road has a unique number and is subdivided
into segments that also have a unique number WITHIN that road (ie. a
Segment is uniquely defined by BOTH its Road number and Segment
number).  A typical table looks like this:

ROAD            SEGMENT         DAILYTRAFFIC    LENGTH
1               1               2100            1.2
1               2               1950            1.0
1               3               2360            1.1
2               1               400             1.4
2               2               450             1.2
etc

I also have a map in which the roads consist of multiple polygons
(regions).  In the map's table I have coded each polygon with a ROAD
number in one field and a SEGMENT number in a second field.  So, a
Segment consists of multiple polygons and a Road consists of multiple
Segments.  My task is to associate my data (above) with the fields in
the map's table. 

Before I can Geocode, I need to combine the individual polygons that
make up each Segment into one object, so that MI can Geocode on a
one_object-to-one_record basis.  As you can only Combine By Column using
one field I have created a third field in the map's table to aggregate
the ROAD and SEGMENT fields
[ThirdField=FormatNumber$(ROAD)+"_"+FormatNumber$(SEGMENT)].  Combine By
Column works fine using this new field.  But, since I have stored the
results in the map's table I now have both the original and the combined
objects overlaying one another on the map (the InfoTool indicates 2
objects in 1 table).  Is it possible to use the Combine By Columns
command to REPLACE the combined objects rather than just create new map
objects?  Am I doing this wrong? (Note: I have tried storing the results
in a different table but this did not copy across the map objects).

If I do get all the polygons in each Segment grouped as one object I
still have a problem with the geocoding.  Geocoding SEGMENT in my data
table to SEGMENT in the map table won't work because values in the
SEGMENT field are not unique to each record (eg. Road 1 has a Segment 1
but so does Road 2 and Road 3 etc).  I need to geocode using both the
SEGMENT and ROAD fields.  MapInfo won't allow me to use ROAD as a
'boundary' field because ROAD is not considered a boundary. Any
suggestions?  I would prefer not to create an additional field in mydata
that aggregates the Road and Segment numbers (like above) as I have
numerous tables of data.

Yes, I have used the Join function (mydata.ROAD=map.ROAD AND
mydata.SEGMENT=map.SEGMENT) to create a third table of joined data and
this works OK.  However, I have numerous tables of data and would prefer
to keep my data outside MapInfo in a RDBMS rather than copy it into
MapInfo.

Any suggestions, references, MapBasic routines, mantras, etc (anything,
really) would be greatly appreciated. Many thanks to anyone who could be
bothered reading this far.

Luke Finnegan
Armidale-Dumaresq Council
NSW, Australia
[EMAIL PROTECTED]

PS.  I'm using MapInfo 5.5
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