MAINT: Add TODO for queries

src/caosdb/transaction.cpp

@@ -180,6 +180,8 @@ auto Transaction::RetrieveById(const std::string &id) noexcept -> StatusCode {
   return this->status.GetCode();
 }
 
+// TODO(fspreck) What about count queries (mixed with retrievals),
+// what about unique queries?
 auto Transaction::Query(const std::string &query) noexcept -> StatusCode {
   ASSERT_CAN_ADD_QUERY