topic Re: Dissolve problem in Data Management Questions

Dissolve problem

GarretDuffy — Mon, 13 Dec 2010 11:44:04 GMT

Hi,
I have a stream line feature class where multiple lines are called the same name (the stream name). I would like to dissolve this feature class using river_name as the attribute.
However, I just end up with an empty dissolved feautre class. I checked multipart features (because I'm not sure if nodes are coincident) but no joy.
Please help!
thanks.
Garret

Re: Dissolve problem

DonovanCameron — Mon, 13 Dec 2010 14:19:02 GMT

Hey Garrett,

can you check to see that your attribute table is formatted correctly?
Look at the [river_name] field, verify that the contents are all stored as Text, not numbers.
Either right click the column header and go to properties; storage format is in here.

Are you getting any errors? Or just "Empty Output Generated" message?

If you are allowed to, provide a snippet of the data here so that other users can troubleshoot or state the data source. That way, if anyone who is familiar with that specific dataset, they can offer some advice.

Re: Dissolve problem

GarretDuffy — Mon, 13 Dec 2010 17:24:54 GMT

Hi Donovan,

Thanks. From your reply, I guessed I was on the right track so I extracted a single set of river lines into a separate feature class and dissolve worked worked fine.

So I'm guessing it must be the size of the original rivers feature class? (it's only 4630 rows and 12 columns though). Should I split it or something?

Thanks for any suggestions,

Garret

Re: Dissolve problem

DonovanCameron — Mon, 13 Dec 2010 17:52:25 GMT

I've experienced something similar with Empty Outputs Generated from tools like dissolve, union, merge when the shapes have too many features.

What constitutes too many features could be anything from the shapefile technical standards, software or harware limitations, to the good old glitch/bug.

When I experience these errors, I will set up the operation in model builder (add your inputs, tools, set up parameters, validate entire model) and export to python script which I run outside of ArcGIS in a cmd prompt, or the python command line. I can compare results, and even productivity.

And like you've already tried, do this same process when using different output and input types: ie, shapefile vs feature class (gdb feature).

Re: Dissolve problem

GarretDuffy — Mon, 13 Dec 2010 18:23:11 GMT

Hi Donovan,

You helped a lot, thanks... your last point was the key. All I did was re-export the original shapefile feature class (which was not made with Arc 10) to another shapefile in Arc Catalog... so, in essence, just made a duplicate, ran Dissolve and it worked! The issue was probably the shapefile format was old.

Thanks a mill...

Garret