Comparing a date to a list of dates

[icarecenter]

I have a list of dates with a y/n column.

I want to check the date in this row with another sheet that has a list of dates.

One one sheet, I have a travel log of dates.

Second sheet, I have my statement of dates that I used the toll.

I want to flag the dates I use toll on that travel log sheet.  I'm not sure how to compare a date to a list of dates.

Can somebody help?

[icarecenter · Accepted solution]

So this works but in order for it to compute, I have to open each one, edit, and save.  I don't need to change anything but it won't calculate an existing set of data.  It will probably update new data.  Is there another way where I can run this expression on a list already?