Compare Two Dates

I need to analyze a system log to determine whether former employees have attempted to access system resources post-separation. Is there an easy way to do this in Exploratory? I’ve joined the appropriate CSV files and mutated the values to like data types.

I’ve completed the task in Excel using a formula and filtering, but I’d rather work in Exploratory moving forward. Any suggestions would be appreciated!

How about creating a data frame one row of which represents an employee?
In that table, I would have the employee’s separation date and last access date to the system.
Then, by comparing the separation date column and last access date column, you would be able to detect access by already separated former employees.
To create such a table from log, you can apply group_by with employee id, then summarize with max(access_date) after that. Then maybe join this table with another table that has employee’s separation date.