Start and end dates for project determined by child tasks

[James_Jensen]

Hi, I’m new to Airtable and loving it so far. I’m wondering if someone can help me with something (which I assume will require a formula). I’m using the project tracker template. I’d like start and end dates for each project to be determined by the start and end dates of the child tasks within that project. So it would have to find the earliest start date and latest end date within all child tasks for that project. Possible? Thanks in advance for your wisdom!

[Jeremy_Oglesby]

I assume the child tasks are linked records, so based on that assumption…

In your Project table, create a Rollup field that points to the Tasks table, the “Start Date” field, and uses the MIN(values) rollup function. This will be your Project start date (the earliest date found among all linked Tasks).

Then create another Rollup field that points to the Tasks table, and the “End Date” field, and uses the MAX(values) rollup function. This will be your Project end date (the latest date found among all linked Tasks).

[James_Jensen]

Genius! It works. And thanks for the ridiculously fast reply.