For example Data1(has 1 billion records) user_id1 feature1 user_id1 feature2
Data2(has 1 billion records) user_id1 feature3 Data3(has 1 billion records) user_id1 feature4 user_id1 feature5 ... user_id1 feature100 I want to get the result as follow user_id1 feature1 feature2 feature3 feature4 feature5...feature100 Is there a more efficient way except join? Thanks!
