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Someone is sending me a CSV file with a list of points that I am trying to map. But instead of the usual Lat and Long there is just a Geometry field (see examples below). I have tried several methods to open this, assuming 3857 is the EPSG - not sure what the 2001 is for. How can I plot these coordinates on a map in QGIS? I have asked for a new file with the usual Lat and Long but would like to try and figure this out while I wait for it if possible.

(2001, 3857, (-8863473.81677258, 5417238.01101921, ), , )
(2001, 3857, (-9247508.24889085, 5207353.52931172, ), , )
(2001, 3857, (-9243598.70837419, 5208396.74498673, ), , )

enter image description here

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This seems to be a slightly modified version of Oracle's SDO_GEOMETRY (see https://docs.oracle.com/database/121/SPATL/sdo_geometry-object-type.htm#SPATL494 for documentation).

The 2001 means every entry is a 2 dimensional point. The 3857 indeed means the SRS is EPSG:3857. The 2 varying numbers should therefore be the x and y coordinates in this SRS.

What is unusual is that when I have had the (mis)fortune of coming across geometry specified this way rather than today's more common WKT, etc., it has been labeled SDO_GEOMETRY rather than GEOMETRY as in your file.

I doubt it will work, but worth a try to just replace GEOMETRY with SDO_GEOMETRY and see if the CSV reading functionality of QGIS might then be able to handle it.

Failing that, I'd import it as a point layer in EPSG:3857, and then use field calculator to update the geometry field using geom_from_wkt and regexp_substr or a similar ad-hoc parsing algorighm.

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  • yes it is exported from an Oracle DB. The SDO suggestion didn't work, I will try the field calculator. thank you for your reply!!
    – WSeanMac
    Apr 26 '20 at 23:39
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    If all the points are exactly the same format and with same number of digits, then geom_from_wkt(replace('POINT('||left(right("SDO_Geom_String",43),35)||')',',',''))) should do it if you don't feel like mucking around with regular expressions. Lops off the junk at left and right, kills the comma between x and y, and recasts it as WKT and then a geometry.
    – Houska
    Apr 27 '20 at 0:45
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    thank you! ended up just fixing the original query in Oracle to include {SDO_CS.TRANSFORM(slb.geometry, 4326).SDO_POINT.y AS latitude, SDO_CS.TRANSFORM(slb.geometry, 4326).SDO_POINT.x AS longitude}
    – WSeanMac
    May 5 '20 at 17:13

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