I have a question regarding Impala UDF (written in Java).
Is there a way to call built-in Impala UDF function (i.e. effective_user) from Impala UDF ?
@Brian100 not in general.
We do actually expose the effective user via the FunctionContext for your use case though - see https://github.com/apache/impala/blob/c14a0904005ce150e15820c8bb9ade94fb58ed56/be/src/udf/udf.h#L134