Complex query returns the samples according to the new Sample model, but it accepts the field names in the query expression only from the OldSample model during the validation. This patch adds translation between the old and new field names and translates the field names to the format of the DB model. Closes-bug: #1291415 Change-Id: I8ef71b6d43b82cd75f0d7a6ea08cdc8881ca62d3