Warning message for "Cannot construct Dataset since there are not use…

…ful features" (#957)

* Update dataset.cpp

* Update dataset.cpp

src/io/dataset.cpp

@@ -226,7 +226,10 @@ void Dataset::Construct(
     }
   }
   if (used_features.empty()) {
-    Log::Fatal("Cannot construct Dataset since there are not useful features.");
+    Log::Fatal("Cannot construct Dataset since there are not useful features. \
+                It should be at least two unique rows. \
+                If the num_row (num_data) is small, you can set min_data=1 and min_data_in_bin=1 to fix this. \
+                Otherwise please make sure you are using the right dataset.");
   }
   auto features_in_group = NoGroup(used_features);