Linked Databases: Displaying & Filtering Data Across Pages

1. The "Single Source of Truth" Philosophy

In Notion, it’s a best practice to keep related information in one large, master database. For example, instead of having a separate task database for each project, you have one master Tasks database for everything. This is called the "single source of truth" principle.

Why is this important?

• Consistency: All tasks have the same properties and structure.
• Power: You can create high-level rollups and relations across all your work.
• Maintenance: You only have one database to manage and update.

But if all your tasks are in one giant database, how do you see just the relevant pieces? The answer is Linked Databases.

A linked database is not a copy; it's a live portal or a window into your original database. You can place these windows anywhere in your workspace and customize each one to show exactly what you need.

To start, let's watch a short, official overview from Notion that introduces this powerful concept.

2. How Linked Databases Work: The Two Golden Rules

When you work with linked databases, there are two simple but critical rules to remember:

1. Content and Property Changes are GLOBAL. If you change a task's name, update its status, or modify a property's value in a linked view, that change is reflected in the original database and every other linked view. You are editing the source data.
2. View Settings are LOCAL. Filters, sorts, grouping, and the layout (Table, Board, etc.) you apply to a linked database only affect that specific instance. This is the magic! It allows you to create countless custom views without altering the original database or any other views.

Creating a Linked Database

You can create a linked database in two primary ways:

• Type /linked view of a database and select your source database.
• Type /table, /board, or any other view type. In the menu that appears, instead of creating a "New database," select your existing master database from the list.

The video below demonstrates this process and reinforces the "global data, local view" principle. It also shows a powerful feature: when you add a new page to a filtered linked view, it automatically gets the properties defined by that filter.

3. Building a Dynamic Project Dashboard

Let's apply this to the connected Projects and Tasks system you've been building. One of the most common and valuable use cases for linked databases is to create a dynamic task list inside each project page.

1. Navigate to your Projects database and open one of the project pages (e.g., "Website Redesign").
2. Inside the page body, type /linked view and select your Tasks database as the source.
3. You will now see a complete list of all your tasks. This isn't very useful yet.
4. Click the Filter button at the top-right of the new linked database.
5. Set the filter to where the Project property (your relation) Contains the name of the project page you are currently on (e.g., "Website Redesign").

Voila! You now have a view that shows only the tasks associated with this specific project, right on the project's homepage. If you add a new task using this view's "New" button, it will automatically be related to this project. Repeat this for your other projects, and each one will have its own self-contained task list, all drawing from your single master Tasks database.

For a detailed walkthrough of this exact process, the following resource is excellent.

✍️ Exercise: Create Your Master Dashboard

Now it's your turn to build the most important page in any personal or professional workspace: a central dashboard.

Goal: Create a new page that acts as your command center, showing you only the tasks that are assigned to you and are currently in progress.

• Create a Dashboard Page: Create a new, blank page in your workspace and title it "My Dashboard".
• Add an Assignee Property: If you haven't already, go to your master Tasks database and add a Person property named Assignee. Assign a few tasks to yourself.
• Create a Linked View: On your "My Dashboard" page, create a linked view of your Tasks database. Choose a List or Table layout for a clean look.
• Apply an Advanced Filter: This is where it gets powerful. We need to filter for two conditions simultaneously.
  • Click Filter → Add advanced filter.
  • Set the first rule to: Assignee Contains Me.
  • Click + Add filter rule.
  • Set the second rule to: Status Is not Done (or whatever you've named your completion status).
  • Ensure the logic between the rules is set to AND.

You should now have a focused list of only your active tasks, pulled from the master database. As you complete tasks elsewhere in Notion, they will automatically disappear from this dashboard view.

Conclusion

You've just learned one of the most fundamental architectural concepts in Notion. By mastering Linked Databases, you can maintain organized, scalable master databases while creating an infinite number of clean, focused, and context-aware dashboards and pages.

Key Takeaways:

• Single Source of Truth: Keep master data in one place for consistency and power.
• Linked Databases are Portals: They are windows into your master data, not copies.
• Global Data, Local Views: Data edits are synced everywhere; filters, sorts, and layouts are unique to each view.
• Filtering is Key: The power of linked databases comes from filtering them to show only relevant information for a specific context (a project, a person, a date range).

In this lesson, you learned to display filtered views of a database in multiple places. But what if you want to display the exact same block of text, or a specific image, on multiple pages and have it update everywhere when you edit it?

In our next lesson, we'll explore Synced Blocks. This feature works alongside linked databases to help you create truly consistent and easy-to-maintain templates and dashboards.