message: fix sqlite fetch schema
diff: @@ -109,6 +109,12 @@ where
  self.names = names;
  self.schema = types.into_iter().map(|t| t.unwrap()).collect();
  return;
  + } else if i == self.queries.len() - 1 {
  + debug!(
  + "cannot get metadata for '{}' due to null value: {:?}",
  + query, types
  + );
  + throw!(SQLiteSourceError::InferTypeFromNull);
  }
  }
  Err(e) => {
  @@ -120,7 +126,7 @@ where
  }
  if i == self.queries.len() - 1 && num_empty < self.queries.len() {
  // tried the last query but still get an error
  - debug!("cannot get metadata for '{}', try next query: {}", query, e);
  + debug!("cannot get metadata for '{}': {}", query, e);
  throw!(e)
  }
  }
  