Hello all,
I've come up with a bit of a problem in terms of MI table linkages.
I'm working with Autocad( .dxf, .dwg, .dbf) maps of a small towns. There are
2 files for each:one with topological info and another without. I've
imported and geocoded both maps into MI, but there's no information
contained in the tables.
In order to link the map to the non-toplogical data, will the Autocad file
have to be opened with an external database program eg)Microsoft Access? If
so what are the required steps.
Also, to make the whole thing more complicated, the map polygons( town
properties) on the Autocad files are labelled with a "PIN" number and I will
have to reference this id tag somehow to a FoxPro dataset which uses
"ADDRESS" to label each polygon. Will I have to dig up another dataset which
links these 2 ids, or is there a way around it with MI?
ANY suggestions much appreciated!
( I"ve attached the similar ArcInfo procedures)
<<RELINKIN.TXT>>
Natalie Swayze
Spectrum/ROS/IC/GC/CA
From: Finnie, Malcolm (NR)
To: '[EMAIL PROTECTED]'
Subject: re: linking your data
Date: Monday, January 24, 2000 10:16AM
Hi Natalie:
Pleased to see things got off to a good start with our data.
I unfortunately have no knowledge of Mapinfo so I'm limited in the
advice I can give you.
Most vendor packages like Arcinfo and AutoCAD have a built in
database creationfunction. That is, once you have built clean
topology, it will allow you to create an external .dbf (database
file) based on the graphics. It will prompt you for what data
entities you want to transfer from the graphics into the tables in
the external database. In the case of our data you would start by
selecting the PIN number as one field you want in the database.
I know in the case of ArcInfo in the build topology phase it computes the
perimiter and area for each polygon. Some packages also compute the
UTM coordinates of the centroid or of the reference mark for the
display label for each polygon. You have a choice of exporting all
of these entities to your external .dbf.
Once you have created your system .dbf you can then import this
data into a secondary database software program like Foxpro or
Microsoft Access. At this stage you have 2 independent sets of tables
in your master database file - the graphics set and your text
database set and you must create some linkage or relationship between
the two. Not always an easy task !
I still think that importing the Stats Canada Area Master file data (ie.
civic addresses) into ourgraphics will do the trick provided you can
place each street address completely withineach of our graphics
polygons. This data - the civic address - then becomes common to
bothexternal databases - the one derived from the graphics and the
Foxpro onecontaining your data. I could take a look at a sample from
your FoxPro data and see if I canspot any other linkage mechanisms if
you wish.
John Leferink or Robert McMahon out at Birds Hill may be able to offer
some further guidance but they too would have to see you Foxpro data
to see exactly what your data looks like that you wish to link to the
graphics - or perhaps your colleagues know some other Mapinfo users
who could help you out.
All the best.
...Malcolm
