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I am trying to view an ESRI FileGDB in QGIS 2.8.1.

Do I have to use "add vector layer" - "directory" - "OpenFileGDB" in order to open and view the data?

Is there a way to specifically open the ESRI FileGDB type in QGIS 2.8.1?

The data I am trying to view is not being displayed correctly. It appears different in other applications. The polylines appear generalized even though I turned off simplify geometry. Two layers in which the polylines should be identical are being displayed differently. The polylines do not match and appear to have different vertices making up the polylines.

I got shapefiles of the same data from the same source and they appear correct. The projection is set to the correct projection in QGIS.

Any ideas on how I can get the ESRI FileGDB to display correctly in QGIS 2.8.1?

QGIS 2.8.1 FileGDB vs SHP

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  • There would be better chance to get an answer if you could share a small FileGDB that could be used for testing.
    – user30184
    Mar 18, 2015 at 20:41
  • The data is publically available data from North Carolina. NC DATA I am looking at the file geodatabases "Road Characteristics Arcs File Geodatabase Format" and "LRS Arcs File Geodatabase Format" The location in my screenshot is in the town of Rocky Mount, NC. State Route 1613 Thomas A Betts Pkwy at State Route 1535 Peele Rd. 36.004988, -77.816690 I looked at the file geodatabase in the free ArcGIS Explorer and free Geomedia Viewer and it looks correct. In QGIS 2.8.1 can it open any file geodatabase?
    – bjy20716
    Mar 18, 2015 at 21:41

1 Answer 1

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Those two geodatabases are separate datasets. Which makes you think that they should match vertex by vertex? What I think is more probable reason is that vectors really differ.

I converted both FileGDB files into shapefiles with ogr2ogr 

ogr2ogr -f "ESRI Shapefile" out.shp rd_char_mlpst.gdb
ogr2ogr -f "ESRI Shapefile" out_2.shp LRS_Arcs.gdb

This image shows the lines and vertices from rd_char_mlpst.gdb close to point 2349780 822977 in EPSG:2264 units.

enter image description here

This one shows data from LRS_Arcs.gdb

enter image description here

LRS_Arcs has longer linestings and less vertices. Most obvious answer is often the right one and geometries in those two datasets really differ. However, if you can proof that LRS_Arcs.gdb has more vertices when you open it with some other program you have probably found some odd bug from GDAL.

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  • I figured out the segments they are using are a circular arc in some locations. Other locations they are straight. In the example above the segments are circular arcs. My guess would be QGIS cannot read a circular arc correctly. Changing a segment into a straight line, a circular arc, or a Bézier curve ICircularArc.Complement Method Image of the Arc
    – bjy20716
    Mar 23, 2015 at 14:15
  • @bjy20716 and user30184 - I found this when researching a more recent question (now linked) with the same issue. Shapefiles do not support any sort of parametric curve - they use line segments to approximate the curve. On the other hand file geodatabases do support true curves. I am not clear on where the issue lies, but it appears that either QGIS itself, the openfgdbdriver, or whatever other method is reading the fgdb cannot correctly read the curve information. That doesn't mean the two layers don't differ, since the same conversion method should produce the same segments from a curve.
    – Chris W
    Jun 12, 2015 at 20:24

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