There’s a lot of conflicting advice out there, especially around the 10-character limit on field name length. We use the most restrictive approach to field naming because we’ve seen the kinds of analytical operations that can be applied to our data in every-day natural resources work. We believe that data that starts out in a legitimate table format (shapefile feature class, geodatabase feature class, INFO file, delimited text file, excel spreadsheet, gpx, etc) should survive conversion to other file types with minimal commotion. We’ve found that these field naming practices help greatly in that regard.
- The maximum length allowed is 10 characters
- Only letters, numbers and underscores are allowed (no spaces, dashes, etc)
- The first character must be a letter (no numbers or underscores)
- Letters should be all capitals (this is strongly recommended by some authors and it’s the practice we follow. To be honest we’ve never seen where the presence of lower case letters has caused a problem).
- Duplicate names are not allowed in the same table
- The following reserved names are not allowed; “data” ,”day”, “month”, “status”, “table”, “text”, “user”, “when”, “where”, “year”, “zone”.