I have a query regarding the dissolving of polygon features in ArcGIS 9.3. I only have the bare-bones license and an extremely basic knowledge of VB.
I have a large shapefile with around 4500 polygons and I want to know if there is anyway of dissolving the ones that overlap? I basically want to turn this layer into a shapefile that contains seperate areas, so where one polygon is on its own it will remain but where multiple polygons overlap they dissolve into 1, with each separate area having its own set of attributes. The shapefile changes quite frequently and up until now I have been going through them all and manually dissolving overlapping areas using the editor tool but I'm sure there's a much quicker way of doing it!
Any insight into how this might be achieved?
I've had a go using the dissolve tool and joining the exported attribute table and this works perfectly! I thought the dissolve tool only worked on attributes and not spatial location so that's extremely useful to know. Also the ModelBuilder code is
Best Answer
I might be missing something, but won't the basic Dissolve tool (somewhere in the data management toolbox) do this for you? No need to mess with any code as in artwork21's answer. Just open the dissolve tool, select your feature class, do not select any field to dissolve on, and then uncheck 'Create Multi-part poygons' otherwise all your poly's will be become one large multi-part poly.
I don't have Arc in front of me right now, but if I'm reading your question correctly, I've done this before using this method. The only concern here is attributes in the table. You know the data, so you'll have to choose how to combine each field in the Statistic Fields part of the tool.
If this process is done extremely frequently or you'd like it done automatically, then do this with model builder and export it to a script, but this tool should take 10 seconds to fill out.