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Sorry for the lack of terminology as it escapes me.

I have a shapefile that contains 96000 individual polygons and I'd like to simplify the shapefile so that it creates 1 polygon. I think it is something like the Region or Aggregate, but only for shapefiles.

Reason being, I have 100s of shapefiles and by using the merge command creates a huge shapefile that contains many smaller polygons of similar features, but I'd like a shapefile to contain just one large polygon. Think of Hawaii being in the middle of the ocean, but it is part of the US, so when selecting any US state (Montana), it also selects the rest of the states along with Hawaii. I also want to retain the original geometry of the individual polygons.

I am running the merge tool right now and it has been running for over two hours and my shapefile is at 2 gb and counting.

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    Shapefiles aren't permitted to exceed 2GB. If you have over 2GB of shapefile data, it's unlikely you'll be able to merge them into one dataset.
    – Vince
    Dec 13, 2020 at 5:11
  • Under some circumstances, shapefiles can be larger than 2GB, but it is not recomended: switchfromshapefile.org/#sizelimit
    – Babel
    Dec 13, 2020 at 9:11

1 Answer 1

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I believe you are looking for the Dissolve (Data Management) tool.

Aggregates features based on specified attributes.

enter image description here

QGIS also has a Dissolve tool:

Vector > GeoProcessing Tools > Dissolve...
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  • Thank you @Aaron for the answer. This worked. However, I have to manually go into each shapefile, add a field and calculate all the records to a similar value, then run dissolve on each shapefile and then at the end, merge all the shapefiles together. The trouble with this is that it is very tedious as I have hundreds of shapefiles I need to run that same process on. If someone could post a model or python script that I could use that could iterate through each shapefile in a workspace and perform the calculate field and dissolve that would be appreciated. My scripting skills are lacking. Dec 13, 2020 at 17:40
  • Are you using ArcGIS or open source tools? I would recommend opening a new question on how to automate this which details the calculation you are making before running the Dissolve operation. In your new question, please make sure to focus on a specific problem and provide a code attempt and any errors you are receiving.
    – Aaron
    Dec 13, 2020 at 18:27

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