Currently in 1.2 I observe the following. 0: jdbc:drill:> select a from dfs.json.`/test.json`; +-------+ | a | +-------+ | null | +———+
But then flatten produces an error 0: jdbc:drill:> select flatten(a) from dfs.json.`/test.json`; Error: SYSTEM ERROR: ClassCastException: Cannot cast org.apache.drill.exec.vector.NullableIntVector to org.apache.drill.exec.vector.complex.RepeatedValueVector Ideally both should return similar responses, in most cases it may be easier to work with a null being returned than no record or an empty string. Returning [] might be interpreted as a string data type pending user experience or tools being used?? —Andries > On Oct 31, 2015, at 4:44 PM, Hsuan Yi Chu <[email protected]> wrote: > > Hi, > For example, say, we are querying a field with empty list: > > select a from `XXX,json` > > { > a: [] > } > > What is the expected result in the sqlline? Which one of the following > should it be? > > 1. [] > 2. null > 3. no record > > Thanks.
