Load * from a REST Connection creates __extra field
I have a load script that requests data from a web service using a REST connection. Below is a small sample of my script..
TableName: Load *; Sql Select Col1,
From JSON (wrap on) "root" With connection ( URL "my/URL/here" );
When I use the Load *, I get this field named __extra in my data model. If I specify the column names instead of a Load *, I do not get this __extra field. For my use case and logic, I must be able to use a Load *. Right now my work around is to just drop that field but I really would like to understand:
1. Why this field, __extra, is coming into my data model?
2. What is this field? (It seems to always be null)
3. Is there a way to use a load * without getting this __extra field? (with out a drop field)