I'm writing this guide because I think the official documentation + productivity gurus' explanations of Notion relations **are inadequate—specifically, they tend to jump straight to a use case for both kinds of relations, rather than first explaining their behaviour, or demonstrating their utility using examples other than parent-tasks connected to child-tasks vs. related-tasks. It might just be that I'm especially dense about this, but one Reddit post shows me I'm not entirely alone.

Here goes nothing.


Relations Between Two Separate Tables

Normally, when we connect two databases in Notion together, both databases each get a new property for the relation—which shows up as a new column in a Table View.

Table 1

Table 2

Three things should be evident from this:

  1. Each row is treated as a single data point — this is a basic feature of Notion databases.

  2. The relation column in Table 1 displays the text from the default, un-deletable Title property column of Table 2.

  3. Vice versa, the relation column in Table 1 displays the Title of related data points in Table 1 — ??which is to say, the relation syncs both ways??


Relations Within the Same Table

Let us consider a new table, Table 3. I will add features to it step-by-step, which should hopefully make things easier to understand.

In Table 3, we create a new relation and choose the option "Use the same property", which Notion displays as below:

https://s3-us-west-2.amazonaws.com/secure.notion-static.com/97935c2f-471b-4e4e-9408-0226d6a71511/Screenshot_2021-03-12_at_23.29.28.png

then we link each of its data points, titled 'Item A/B/C' to each other sequentially:

Table 3.1.1

What happens if I now try to create an 'Item D' directly in the relation column?

Table 3.1.2

As we might expect, this adds a new row (i.e. new data point) for 'Item D' to Table 3.