> > 2016-02-09 16:51 GMT+01:00 Andy Gillett <[email protected]>: > >> *Objective* >> >> I am trying to Dissolve approx. 500,000 polygons which represent a 250m >> buffer around many line segments (e.g. electrical cable network or could be >> a road network). I have 5 buffer distances to create in total. The 500,000 >> polygon shp file is a sub-set (approx. 1/10th) of the entire dataset >> requiring processing in this way. >> >> >> In my experience, Difference is much faster than Dissolve. Create a big polygon around the area containing the buffers. Then run Difference on the polygon layer and the buffer layer, then run it a second time to get the desired result.
Best wishes, Anita
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