English

FAQ: What is the maximum length of a field name in a raster attribute table?

Question

What is the maximum length of a field name in a raster attribute table?

Answer

In ArcGIS 9.2, the possible character-length of a raster attribute field is determined by its underlying table support:

File raster formats, other than GRID, are supported through a dBase file (.vat, .dbf). dBase table field names have a ten-character limit, so the raster attribute tables also have a ten-character limit.

GRID format, supported though a value attribute table (VAT), allows up to 16-character field names. The field length of a geodatabase raster attribute table can be longer, varying with each DBMS. The raster attribute tables for these data formats reflect these field lengths.

Therefore, exporting file raster formats with larger field names to those with ten-character limits, such as a TIFF or an IMAGINE, have attribute tables that are truncated to ten characters.

GRID format, supported though VAT, allows up to 16-character field names. The field length of a geodatabase raster attribute table can be longer, varying with each DBMS. The raster attribute tables for these data formats reflect these field lengths.

Therefore, exporting file raster formats with larger field names to those with ten-character limits, such as a TIFF or an IMAGINE, have attribute tables that are truncated to ten characters.