For Avro files, we first construct the schema, and this schema is used for validating queries. So, if there are any errors in the query (like the invalid field references) it will fail fast. As of now, for other file formats, query validation (checking for invalid field reference) does not happen, and at run time, it constructs the schema for them and hence nulls for invalid fields.
On Mon, Dec 14, 2015 at 2:36 PM, Stefán Baxter <ste...@activitystream.com> wrote: > Hi, > > I'm getting the following error when querying Avro files: > > Error: VALIDATION ERROR: From line 1, column 48 to line 1, column 57: > Column 'some_col' not found in any table > > It's true that the field is in none of the tables I'm targeting, in that > particular query, but that does not mean that it is in none of the possible > files I could be querying. > > We use Avro to get the benefits of the schema but I never expected Drill to > enforce it this way. > > Why do unresolved columns not return null? > > This makes no sense to me as I think a fundamental trade of Drill, when > trying to eliminate ETL, is to return null for any missing fields. > > Please advise. > > Regards, > -Stefán > -- Kamesh.
