Notion's distinctive advantage is its unique integration of databases and documents. The
Rollup properties make that feature even more powerful. They're part of any sophisticated workspace and the cornerstone of the Bulletproof methodology.
Relation property allows you to connect database items. When you create a
Relation, you link it to a database. That allows you to choose items from that linked database to populate the property, somewhat like a
Select property. Typically, you'll link
Relations to other databases, but sometimes you'll choose the same database.
Related database items often represent parent-child relationships, where one item—the "parent"—is the classification, or grouping, of its related items—its "children."
For example, a Companies database often relates to a Contacts database. For each contact, you can choose the employer from Companies. Those contacts are automatically added to the reciprocal
Relation property in Companies:
Here are some other parent-child relationships:
The relationship can also be non-hierarchical:
Relationproperty would link to the same database.
Often used in place of
Relations offer expansive benefits. These are among the most notable:
By choosing a value from a central repository (the linked database), you ensure it's entered the same way everywhere in your workspace.
Consider our Companies and Contacts databases. With a
Text property, you're inclined to enter the same company in various ways, such as "Walmart" vs. "Wal-Mart." Among other consequences, this disrupts sorting and filtering.
Relation, you choose Walmart from the centralized Companies database:
Choosing from a central collection also eliminates the need to type inputs and create duplicate
In addition to the Contacts database, many other databases are likely to reference a company. For example, an Expenses database will have a Vendor property. Rather than creating identical
Select properties in Contacts and Expenses, you can relate them to the Companies database, thus retaining a central repository:
You'll often want to filter "child" databases by their "parents." For example, you'll want to view players by team and tasks by project. Using
Relations and database templates, you can automatically filter children within their parents.
In our Companies database, the template can filter Contacts to show only the employees of the respective company:
Rollup property allows you to aggregate information from related items. You can then perform calculations on that information to reveal useful insights.
A common parent-child relationship is Expense Categories and Expenses. A
Rollup can total the expenses related to each category:
Easily click items within a
Relation property to open them as pages.
When viewing a company, for example, you can easily open an employee's profile:
Most often, you'll establish relations between separate databases:
Relationproperty to reflect the other database.
Relationin the other database. Rename it accordingly.
Once in place, you can use that
Relation property to choose items from the other database.
Less frequently, you'll relate items to other items in the same database. A common example is dependent tasks, where Task B depends on Task A. The process for creating these
Relations is the same; you simply choose the same database.
When doing so, you're given the option to form a two-way relationship ("sync both ways") or a one-way relationship ("no syncing"). A two-way relationship creates a reciprocal
Relation property within the same database, while a one-way relationship keeps only one
Relation property. For parent-child relationships, you'll typically want the reciprocity. They're still helpful, but not always essential, for non-hierarchical relationships, like dependent tasks.
Relations. They retrieve and aggregate other properties from related items, then perform insightful calculations on those values.
Revisiting our Expenses and Expense Categories databases, each category relates to multiple expenses, then a
Rollup sums the Total property of those expense:
Rollups can perform a variety of calculations on the values they retrieve. Some of those calculations are specific to the value type, such as numbers, dates and checkboxes. Here are the calculations used most frequently:
Rollups retrieve information from related items, they require an existing
Relation property. Once you have that in place:
Rollupis added to Expense Categories. It's the "parent" that groups and summarizes the individual expenses.
Rollupproperty, as if to enter a value. You'll see three configuration settings:
Relation, choose the
Relationproperty for which you want to retrieve information.
Property, choose the property of the related database you'd like to retrieve. From Expenses, we're retrieving the Total property for all related items.
Calculate, indicate how to display the retrieved values. With the retrieved Totals, we
In our Companies example, a
Rollup can calculate the average age of employees (related contacts):
Rollup is configured like so:
Propertyis Age (the property of Contacts we want to retrieve).
Calculateis set to
Checkboxes, it can calculate the percent checked. Therefore, a project can display its progress as the percent of completed tasks:
Within our Projects database, a
Rollup is configured like so:
Propertyis Complete (the
Checkboxproperty we want to retrieve).
Calculateis set to
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