Merge multiple shapefiles (year to year, for example) and append attribute table to include original file name (for categorization)

merge.sh

for f in *.shp
do 
  base=${f%.shp}
  ogrinfo $f -sql "ALTER TABLE $base ADD COLUMN filename character(15)"
  ogrinfo $f -dialect SQLite -sql "UPDATE $base SET filename = '$base'"
  ogr2ogr -update -append merged.shp $f
done