Asking for advice, there is one thing that needs to be checked, which is shown in the figure. I want to compare the names of the people on Friday with those of the previous 4 days. If there is no repetition, it will be displayed. How to write this mysql statement?
The results I hope to get are Peter and Mary. But I don’t know how to write this mysql statement. Thank you
Select Name From tbl Where? date = 'Fri' AND NAME NOT IN( Select Name From tbl Where? date IN('Mon', 'Tue', 'Wed', 'Thu') )
The stupid way is like this, when there is a lot of user data, there will be efficiency problems.