Comparing dates and linking records between two tables

Hi airtable community!

We teach classes and utilize Airtable as our class schedule. I am attempting to create a new table that sums the number of attendees for each class by the class type and date/time.

We currently have an attendees table which contains the individual reservations and another table called class totals which contains a record for each event. I am able to achieve a total by using a rollup field with Sum(values).

Is there a way to use automations to link these records automatically? I utilized the “Link Records by Field” app to do the initial linking but it would make a lot more sense if it was an automation.

Hi Little Glass Art, apologies but I can’t really picture your set up and what you’re trying to achieve, if you could share some screenshots of your base set up I could try to provide some suggestions

Happy too! Here is an example of both our attendees and class totals table. The automation would link each individual reservation on the attendees table to the corresponding date, time and class type on the class totals table so that I can quickly see we have 14 people for our mini lead class on 5/21 @ 4:00pm.

In the end, I hope to use it in combination with Integromat to automatically close classes on our website. Because we get both call-in and online signups we can quickly become overbooked if we do not act fast enough to close online registration.


Ah! Thank you very much for the explanation, I understand now!

Accomplishing this requires a bit of a workaround as automations don’t let you find a record by comparing the dates (as far as I know!). To deal with this, I created a formula field with the formula as:

{Date} & ''

This effectively converted the date to a string, and so we can now compare the date value between two tables. I’m worried about the possibility of two events happening at the same time at different locations, and so I think we should add in a check for whether the Event Title in Class Totals matches the Event in Attendees

I’ve put up a working copy here


If you’re free, may I know how you populate the Attendees table? I was thinking that it might be easier to do the link during the record creation process instead. We could filter the classes available for selection as records by limiting it to a view so that it’s easier to select the right classes

I’ve put up this alternative version here