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I have been looking into reducing the dataset as much as possible.  My customers are mobile customers and will do updates over wireless WAN connections, which, as good as they are these days, are still not good for downloading massive amounts of data.

I found this post where someone is having a similar problem.  I have already done something similar to this for Texas and have a resulting data folder of about 2.16 GB.  My customers are law enforcement officers and so they generally stay within a given jursidiction.  What would be ideal would if I could easily filter this data into county specific layers.

My sales rep and I discussed this at one point. He contacted the development team and I received this response:

“I think there are some easy things he can do to shrink it down further assuming he doesn’t need a lot of the information in the dbf.

 

Typically the DBF files are some of the largest, in Render USA they contain a lot of data that most people don’t need.  In fact probably for his purposes all he really needs is the street name so it can be labeled and the recid.  What I would propose is that he takes a tool like DBF Manager and removes the unneeded columns in the TLKA, CTYCU & WAT folders for his given state.  I think will shrink the data down considerably.

 

He will probably want to back up the original files in case he ever wants to use those other column in the future.”

The problem I am having is that I don't have the data model information to understand what columns I need, or even to explore if I could create my own county based layer files.

I don't like to hunt and peck at data and model changes, so is there someplace I can get data model info?

Thank you!

Karl

Karl,

Thanks for your question! The easiest way to to see the dbf informtion of the Render USA shapefiles is through Map Suite Explorer. By loading a layer into Map Suite Explorer you can choose the 'Tabular Data' and view every field in the DBF.

Hope this helps!

ThinkGeo Support

Ryan,

With MS Access as well, I can see the data fields, I just don't have any description of what each column means, therefore I cannot judge the impact of removing a given column to reduce the dataset size.

Karl

Karl,

I think I can save you a lot of work. In the World Map Kit 3.0 Beta we have reduced the size of the data quite a bit by removing the unecessary columns in the DBF. Since you have Render USA you can contact your salesman and get a new World Map Kit DVD shipped out to you at no additional cost.

Then all you would need to do is replace the WAT, TLK, (This is where the bulk of the size is taken up) and other USA Specific folders in your current Render USA directory structure and you will get the benefit of the smaller dataset. One thing I'm not sure of is if you will need to rebuild the IDX files since these were built using 3.0. If the data doesn't load correclty then you may have to remove all the IDX & MDX extensions and then write a little app to rebuild them using the BuildIndex method off of the layer.

If you have any questions let us know.

Thanks!