How to Add Comments on Table Column in Tableau

Adding a definition or bit of context to a column in a Tableau dashboard seems like it should be simple, but there's no obvious "Add Comment" button. This article breaks down several practical and effective methods for documenting your data fields, both for your own reference and for your end-users. We’ll cover everything from built-in metadata features to creative dashboard techniques.

Why Add Comments or Definitions to Your Table Columns?

Before we jump into the "how," let's quickly cover the "why." Documenting your data is critical for a couple of key reasons. First, it ensures clarity and consistency. Does "Sales" mean gross revenue or net revenue after discounts? A quick comment can save hours of confusion and prevent stakeholders from making decisions based on misinterpreted data. Second, it makes onboarding much smoother. New team members can understand the dashboard's data fields without having to constantly ask what each column means, making them self-sufficient faster. Clear definitions are the foundation of good data governance and a truly data-driven culture.

Method 1: Using the Built-in Metadata Comment Feature

Tableau actually has a built-in feature for adding comments, but it's intended more for internal documentation than for display on a public dashboard. It’s perfect for notes to yourself or other Tableau developers about how a field is calculated or where it originates.

How to Use It:

1. Navigate to the Data Source tab at the bottom left of your Tableau workbook.
2. In the top right of the metadata grid view, you might see your fields displayed as a list or a grid. Click the grid icon to switch to the list view, which makes fields easier to manage.
3. Find the column (or field) you want to comment on in the list. When you click it, a properties pane will appear on the right side.
4. In this properties pane, you'll see a field labeled "Comment." Simply type your definition, calculation logic, or any other important context here.

The comment you add is now saved with that field's metadata. You can see it here in the Data Source tab, and often you can see it by hovering over the field name in the Data pane on the left side of a worksheet.

• Pros: This is the fastest, simplest, and most "official" way to document a field within Tableau itself. It requires no workarounds and is great for developer notes.
• Cons: The major drawback is that this comment is not visible to the end-users viewing the published dashboard. It’s strictly for creators working inside the Tableau workbook.

Method 2: Creative Tooltips for On-Hover Context

If you need your audience to see the definitions on the actual dashboard, tooltips are your best bet. This method creates a premium user experience where a user can simply hover their mouse over a column header to get a pop-up explanation.

This technique is a bit more involved because you have to 'trick' Tableau into creating a header that you have full control over. You’ll create a separate worksheet for your header and then add it to your dashboard.

How to Do it Step-by-Step:

Step 1: Create Your Data Table Sheet

First, build your main data table on a worksheet as you normally would. For this example, let's say you have a table showing Region and Sales.

Step 2: Create a Dedicated "Header" Sheet

Now, create a new worksheet that will act as the interactive header for your Sales column.

1. Create a new calculated field called something like "Sales Header Title." The formula is just the name of the header in quotes: "Sales"
2. Create a second calculated field for your comment, let's call it "Sales Definition." The formula contains your descriptive text: "Represents net sales in USD after all discounts and returns have been applied."
3. Drag the "Sales Header Title" calculated field onto the Text card in the Marks pane.
4. Drag the "Sales Definition" calculated field onto the Tooltip card.
5. Click on the Tooltip card to edit it. By default, it will show both the title and the definition. Clean it up so it just shows the definition, or format it however you like. You can make the text bold, change colors, etc.
6. Finally, format this worksheet to look like a header. Right-click on the sheet and select "Format" to remove grid lines, borders, and change the font to match your dashboard's style.

Step 3: Combine Them on a Dashboard

1. Create a new dashboard.
2. Drag your main data table sheet onto the dashboard.
3. Right-click the title of your data table sheet and select "Hide Title." Standard titles don't allow for tooltips, which is why we're making our own.
4. Now, drag your new "Header" sheet onto the dashboard and place it directly above the corresponding column in your main table. You might need to use a Horizontal container object to get the alignment just right.
5. Adjust the sizing to make it look like a seamless header.

Now, when a user hovers over the "Sales" header you've created, the definition will pop up in the tooltip!

• Pros: This provides an intuitive, interactive experience for end-users, delivering context exactly where and when they need it without cluttering the screen.
• Cons: It requires creating an extra worksheet for every column you want to annotate, which can be tedious for wide tables. Aligning the headers perfectly can also be tricky.

Method 3: Using an "Information" Icon and Dashboard Actions

This is probably the most professional-looking method. It involves placing a small icon (like a '?' or 'i') next to a column header. When a user clicks or hovers over the icon, a perfectly formatted text box with the definition appears.

How to Do it Step-by-Step:

Step 1: Create an "Information Text" Sheet

First, create a worksheet that will serve as the pop-up information box.

1. Create a new worksheet.
2. Create a calculated field containing the detailed comment you want to show for a column, for instance, "Profit Ratio Definition." Formula: "The Profit Ratio is calculated as (Profit / Sales). A higher ratio indicates better performance. This field excludes returns."
3. Drag this calculated field to the Text card.
4. Format the text to be clear and readable. Give the sheet a simple, descriptive name like "Profit Ratio Help".

Step 2: Create the Icon Sheet

Next, create the tiny sheet that will just hold our clickable icon.

1. Create a new worksheet named "Info Icon."
2. In the Marks pane, change the type from "Automatic" to Shape.
3. Click on the Shape card and choose a shape that looks like an info icon. The "Filled" palette has a good 'i' icon.
4. To keep the icon from being too big, an easy trick is to type an ad-hoc calculation in the Columns or Rows shelf like MIN(0). Right-click this pill and uncheck "Show Header" to hide the axis.

Step 3: Assemble and Activate on the Dashboard

1. Go to your dashboard. Drag your main visualization, the "Profit Ratio Help" sheet, and the "Info Icon" sheet onto the canvas.
2. Using a Floating object, place the "Info Icon" sheet exactly where you want it - right next to the column header.
3. Add an Action:
4. You can style the button to look like an image (your 'i' icon) or text.
5. When clicked, this will "navigate" to the sheet containing the info, or toggle its visibility if using zone/parameter actions. Users can simply go back to the previous screen or close the info popup.

This makes for an extremely clean and guided user experience, allowing for very rich text explanations without cluttering the main view.

• Pros: Extremely professional and clean. Can hold a large amount of formatted text. Ideal for complex definitions or instructions.
• Cons: Has the highest learning curve, requiring familiarity with floating objects and dashboard actions or zone visibility.

Final Thoughts

While Tableau may not offer a straightforward "comment on this column" button, you have powerful options to provide critical context. Using the metadata pane serves as excellent internal documentation, while custom tooltips and info icons create a fantastic, interactive experience for your stakeholders, making your dashboards clearer and more impactful.

Of course, the need for these comments often arises because dashboards themselves can be complex to interpret. At Graphed we help you skip the complexity altogether. Instead of building intricate tables that require detailed comments sections, our platform allows anyone on your team to connect their data sources and simply ask questions in plain English. This conversational approach eliminates the ambiguity, delivering instant charts and insights directly, so you spend less time documenting data and more time acting on it.