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Given a .shp that covers the globe, how could QGIS be used to segment that into 90 .shp files, each file containing lines/points/polygons/multipolygons that are between the first and second then second and third then third and fourth, etc?

Issue is a series of gigantic source files with global coverage that have no common attributes that would allow them to be conventionally partitioned. Since the source files have a relatively even distribution (not over the Pacific ocean of course), cutting them up into smaller files will make them cleaner to process.

I was hoping there was a hidden command in ogr2ogr that would do this, but I don't see one.

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You can use the -spat option of ogr2ogr and a loop to do this. On a linux box I'd do something like:

for x in `seq -180 10 170`; do
     x2=$((x+10))
     ogr2ogr -spat $x -90 $x2 90 -spat_srs epsg:4326 outfile_$x.json infile.shp
done
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  • Experimenting with this, good idea! What does "Warning 1: cannot determine layer SRS for myshape" mean? I am confused about the -spat_srs switch. This works but I think I am introducing errors: ogr2ogr -progress -overwrite -lco RFC7946=YES -f GeoJSON -s_srs "EPSG: 3857" -t_srs crs:84 -spat -180 -90 -170 90 piece1.json piecesall.shp
    – Snowy
    Commented Aug 19, 2020 at 21:56
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    That means your shapefile lacks a prj file - use -a_srs to set the projection for the input file. -spat_srs defines the projection of the spat coordinates
    – Ian Turton
    Commented Aug 20, 2020 at 7:15

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