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We have around 60,000 separate shp - tab files. We have to move all those into a gdb. While doing so, at times the data are getting duplicated as shown in the fig. Lyr_1 - gdb layer. Lyr_2 - individual shp file. We have to identify the duplicates of Lyr_2 in Lyr_1(gdb) and give unique id's to that features in Lyr_2.

Curretnly, we are using Xtools pro for ArcGIS -> Find duplicates option to identify the duplicates. ArcGIS -> Select by location -> are identical to source feature layers is not working. We dont have license to Data Reviewer & Find identical tool.

Is there a way to do this in QGIS ?

Even in QGIS, tried with Spatial query -> features equals. But didn't work enter image description here

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    If you want to know this for QGIS then I think you should focus your question on that. Otherwise you are effectively asking two questions (can ArcGIS for Desktop do this? and can QGIS do this?) which makes this too broad as per the Tour. – PolyGeo Dec 7 '15 at 3:10
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    Ok. I've edited the question – joseph_k Dec 7 '15 at 3:17
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    Spatial equivalence is a touchy issue, because there's a big difference between "equal" and "effectively equal". You may need to go with automation to identify the features that are really similar (that start/stop in the same fine reference grid cells), then manually review the two sources for which feature should be removed. The algorithms to implement this are not software-specific. – Vince Dec 7 '15 at 3:33
  • Could you give a brief on that "automation" part. Would be of great help – joseph_k Dec 7 '15 at 4:02
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You could use the Select by location tool from the Processing Toolbox to identify and select features from Lyr_2 which spatially equals features from Lyr_1:

Select by location tool

Once selected, you could add unique IDs using, for example, the Field Calculator.

Note: Depending on your data, you may need to be careful as this method makes a spatial comparison, it doesn't check if the features are duplicates.

  • Tried that too. But the spatially overlapping features are not getting selected. Will the number of nodes play a part here ? – joseph_k Dec 10 '15 at 8:56
  • @saravanaganesh18 - Perhaps try increasing the precision? Not sure if the number of nodes matter. – Joseph Dec 10 '15 at 10:30

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