Date Tables are Great for Users, but Not So Great for Performance


Date tables help users filter data based on day of week, holiday, this year vs last year, and other kinds of filters that business users usually wanna add to their reports. If you haven’t used a date table before, here are a couple of primers on how to create one and use it:

Creating a date dimension table by Aaron Bertrand How to create a date_calendar table by Sean Smith

And for the purposes of this post, I’m going to use the date_calendar table created in the second bullet point above. Here’s what it looks like:

Typically when people