One approach is to join your data to a date scaffold:
Then you will get a separate room for each scaffold date between check in and check out.
Thank you so much for helping me,
But I have a PostgreSQL's data as a input data not spreadsheet and its real time data, this solution is not worked on my scenario
can you tell me, how I add external date column in my database? (in tableau ), so i get data (occupied room and that room's booking amount) based on that external date
It might be possible to accomplish it with Custom SQL?
Here are some threads that may give ideas: