Thread by @NotionHQ

1/ Relation & rollup are the most powerful features in Notion! This thread is a 3min intro guide 😎

First of all, the world runs on relational databases! Once cutting edge 70s tech, invented by IBM/famously forgotten – til Larry Ellison/Oracle sold it to every bank and gov 😓

2/ Let's start with an example 👇

Imagine you have two databases: customers and products, and you want to them to work together to find out:

- Who bought what?
- How much did they spend, total?

(Example page: notion.so/notion/Databas…)

3/ First step, set up a relation 🍼

In the Customers database, add a property/column → set it to Relation → select the Products database.

Now a customer can relate to one (or more) products! We're going to name this relation "Ordered Products" to keep track.

4/ How to tell the database that Susan ordered "Khaki pants" + "Tank top" ⁉️

Click the Ordered Products cell on the Susan row→ pick a product → confirm with Enter to add those related pages.

(Tip: add multiple products at once by clicking on the blue circle 🔵)

5/ Now we can see all of Susan's orders in a table!

If you want to remove/edit one:
- Click to open an order as a editable page (say, you want to change the price of a product on the fly).
- Click on the red circle to remove an order.

It's keyboard-friendly too 🤓

6/ Notice another column automatically created for you in the Products database? 👀

Relations are two-way in Notion, so when you add "Tank-top" as an order for Susan, we inversely adds "Susan" as a customer in "Tank-top". Super handy👌

7/ Naturally you'll wonder: how much did Susan spend – in total? 🤔

For that you'll need a rollup!

In the Customers database, add a property/column → set it to Rollup → set relation to Ordered Products → set property to Price → set Calculate to SUM.

Powerful right? 😋

8/ There are 14 kinds of rollups as of today:

Show Original (as known as a lookup), Min, Max, Range (max minus min), Count All... full list: notion.so/notion/Databas…

With relation & rollup, you can solve problems that typically only programmers can solve 💪

9/ Lastly, how can we see the total amount ALL customers have spent?

Move your mouse towards the bottom of a column → you'll see a "Calculate" button → choose SUM.

Calculate and rollup are a powerful combo 👯‍♀️

10/ Hope that gives you a good sense of relation & rollup? They're one of the most powerful features in Notion.

More ideas:
- Tasks & projects
- Companies & contacts
- Job applicants & interviewers
...
Have fun and stay organized! ✌️

Full guide: notion.so/notion/Databas…