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I am trying to join multiple records that occupy the same location (polygon centroid) and have tried using the join by location plug-in but have found this does not work for me in this case as I have more than one (up to 10) records that share the same location.

I am trying to reduce the geometry by appending all records to the one point. Is there a solution in QGIS that can help me achieve this?

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If I understand correctly, you have a polygon layer, and many point layers. You want to spatially join the data from each of the point layers to the polygon attribute table. Is that the case? What differentiates the point data layers? You will need new columns in the polygon attribute table for all the columns in each of the point layers. So if there are 10 point layers with 5 columns each, you'll need 50 new columns in the poly table. If, on the other hand, all the point data are saved in one shape, you'll need some way to split it up. – Micha Dec 13 '12 at 8:18
I have multiple points with different attributes (all on one layer) and some of the points have the same co-ordinates. – Stephen Donaldson Dec 13 '12 at 9:03
I would like to join all the point attributes that have the same location. I.e points 1-5 have co-ords x1,y1 but attributes point1 name: a point2 name: b point3 name: c act. – Stephen Donaldson Dec 13 '12 at 9:08
*ect and i would like to have 1 point with x1,y1 and attributes name1:a name2:b name3:c ect – Stephen Donaldson Dec 13 '12 at 9:09
could you set this out in table or diagram, to help me understand? – Willy Dec 13 '12 at 12:00

From your description it does not sound like you need a spatial join since you could simply join based on the x and y attribute.

But I don't think there is a good way to do that in QGIS. If I understand the description correctly, you are looking for a way to append a potentially very big amount of additional columns to one geometry. That's unusual. Maybe if you would describe what you are trying to achieve by doing that, we could provide a different route.

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I have a DB extract that has records of events that occur at a defined location but do not poses any spatial (X,Y) records. As part of my process I use the MMQGIS Attribute join from CSV file. This then gives me all the records with a location (centroid) but what also results is where events occurred at the centroid with the same "joined" attribute I end up with the scenario above. – Stephen Donaldson Dec 13 '12 at 21:23
This will produce about 700 -750 columns as one record has about 70-75 (Im to lazy to count:-|) – Stephen Donaldson Dec 13 '12 at 21:29

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