Although not documented in the shapefile spec, there are restrictions on DBF attribute table field names (besides the length limit). Restrictions may include but are not limited to:
no spaces
no duplicate field names
field names must begin with alphabetic characters
only alphanumeric characters and underscores allowed
These limitations may have more to do with certain programs (scowls in ESRI's direction) than with the file format itself. Nevertheless, we want to ensure good compatibility, so conform to convention.
Write field name tests for attributes.test.tcl and try to locate authoritative documentation for the DBF version generated by shapelib.
(Only restrict name format when creating/adding fields - if the input is cosmopolitan enough to be cool with spaces in names, we should be so cool too.)
Although not documented in the shapefile spec, there are restrictions on DBF attribute table field names (besides the length limit). Restrictions may include but are not limited to:
These limitations may have more to do with certain programs (scowls in ESRI's direction) than with the file format itself. Nevertheless, we want to ensure good compatibility, so conform to convention.
Write field name tests for attributes.test.tcl and try to locate authoritative documentation for the DBF version generated by shapelib.
(Only restrict name format when creating/adding fields - if the input is cosmopolitan enough to be cool with spaces in names, we should be so cool too.)