> I am using Avro for processing/encoding billions of rows using Hadoop. When I attempted to upgrade to Avro 1.5 I got an error about illegal field names. I notice this case happens when I use a ‘-’ character or a ‘.’ in a field name.
> Are there any other restrictions on fields names I need to know when upgrading?
You can find the full details in the Avro spec . It's basically just like the identifier restrictions in most programming languages. Names can only contain letters, numbers, and underscores, and can't start with a number. Dots are used to created namespaces, just like fully-qualified Java identifiers.