Fill missing timestamps and apply different operations on different columns
问题 I have a data in below format user timestamp flowers total_flowers xyz 01-01-2020 00:05:00 15 15 xyz 01-01-2020 00:10:00 5 20 xyz 01-01-2020 00:15:00 21 41 xyz 01-01-2020 00:35:00 1 42 ... xyz 01-01-2020 11:45:00 57 1029 xyz 01-01-2020 11:55:00 18 1047 Expected Output: user timestamp flowers total_flowers xyz 01-01-2020 00:05:00 15 15 xyz 01-01-2020 00:10:00 5 20 xyz 01-01-2020 00:15:00 21 41 xyz 01-01-2020 00:20:00 0 41 xyz 01-01-2020 00:25:00 0 41 xyz 01-01-2020 00:30:00 0 41 xyz 01-01-2020