Looking at a gpkg problem I created an issue for some time ago:
It appears that QGIS is doing some guessing about the primary key?
Like, IF there is a fid, it is used as PK, but gpkg creation fails when
the original fid is not an integer.
Second: when you (in the QGIS save dialog) empty the 'fid' field (as in
this case, remove fid in the field), creation succeeds, but you end up
with a table in the gpkg with a column with an empty column name ('').
Can others confirm?
Or is this a GDAL issue?
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