Fix Notion Database Cannot Show Sub-Items: Property Compatibility Fix

You created a relation property in a Notion database and expected sub-items to appear in a linked view. Instead, the sub-items column shows nothing or an error. This problem happens because the property types in the source and target databases are not compatible for the sub-items feature. This article explains the property compatibility requirement and gives exact steps to fix the relation so sub-items display correctly.

Notion sub-items require a specific database setup. The relation property that connects two databases must point to a database that uses a primary property type supported by the sub-items system. If the target database uses a formula, rollup, or unsupported property as its primary column, sub-items will not show. You will learn how to check the primary property type, change it if needed, and rebuild the relation to restore sub-items.

This guide covers the root cause of the missing sub-items issue and provides a reliable fix. You will also find related failure patterns and a comparison of supported property types for sub-items.

Why Sub-Items Fail in a Notion Database

Notion sub-items rely on the relation property connecting two databases. When you create a relation, Notion reads the primary property of the target database to display sub-items in a linked database view. The sub-items feature requires the target database to have a primary property that is either a Title property or a Text property. If the primary property is a Formula, Rollup, Select, Date, or any other type, Notion cannot render sub-items. The view shows an empty column or a placeholder without data.

This restriction exists because the sub-items system needs a simple text-based value to display in the parent database. Formula and rollup properties may produce dynamic or aggregated values that change with context, making them unreliable for sub-item display. Select and multi-select properties store predefined options, not user-entered text. Date properties store date objects. None of these types can serve as the visible label for a sub-item row in the parent database view.

The fix requires changing the primary property of the target database to a Title or Text type. After the change, you must delete the existing relation property and create it again. Simply editing the relation property does not refresh the sub-item display. Re-creating the relation forces Notion to re-evaluate the target database primary property and enables sub-items.

Steps to Fix Sub-Items by Changing the Primary Property

1. Open the target database in full page view
   Click the name of the target database in the sidebar or in a linked database view. The target database is the one that contains the records you want to show as sub-items in the parent database.
2. Check the current primary property
   Hover over the column header that shows the name of each row. The primary property is the first column in the database by default. Look at the property type icon next to the column name. If the icon shows a formula symbol (fx), a calendar, a tag, or a number, the property type is not supported for sub-items.
3. Add a new Title or Text property
   Click the plus icon in the last column header. Select Title or Text from the property type menu. Name the property something like “Item Name” or “Sub-Item Label.” This new property will become the primary property after the next step.
4. Set the new property as the primary property
   Drag the new Title or Text column to the first position in the database. Notion automatically designates the first column as the primary property. When you move the column to position one, the old primary property moves to the right and becomes a secondary property.
5. Delete the existing relation property in the parent database
   Open the parent database that contains the relation property pointing to the target database. Hover over the relation column header and click the down arrow. Select Delete from the menu. Confirm the deletion when prompted. This step removes the broken relation that prevented sub-items from showing.
6. Create a new relation property
   Click the plus icon in the last column of the parent database. Select Relation from the property type menu. In the relation configuration dialog, choose the target database. Set the relation to show sub-items by checking the box labeled “Show sub-items in this database.” Click Done to create the relation.
7. Verify sub-items appear
   Add a new row in the parent database. In the relation column, click to select a record from the target database. After selection, the sub-items column should display the name of the linked record. If the sub-items column is still empty, repeat steps 5 and 6 ensuring the target database primary property is set to Title or Text.

If Notion Still Has Issues After the Main Fix

Relation property shows but sub-items column is blank

This happens when the target database has a Title or Text primary property but the relation was created before the property change. The old relation cached the incompatible property type. Delete the relation property and create a new one as described in steps 5 and 6. Do not edit the existing relation — deletion is required.

Sub-items show only partial data

If sub-items appear for some rows but not others, the target database may contain empty values in the primary property column. Notion cannot display a sub-item row when the primary property cell is blank. Open the target database and fill every row with a value in the Title or Text primary column. Use a unique identifier like a task name or a product code for each row.

Cannot move a formula or rollup column out of first position

Some database views lock the primary column position. Switch to a different view type, such as Table view from the view menu. In Table view, you can drag any column to the first position. After moving the formula column to position two, set a Title or Text column as the new primary column. Then switch back to your preferred view.

Supported Primary Property Types for Sub-Items

Property Type	Supports Sub-Items	Notes
Title	Yes	Default primary property type
Text	Yes	Works as primary property after manual change
Formula	No	Dynamic output incompatible with sub-item display
Rollup	No	Aggregated values cannot serve as row labels
Select	No	Predefined options not suitable for sub-item labels
Multi-Select	No	Multiple values cause display conflicts
Date	No	Date format not supported as primary property for sub-items
Number	No	Numeric values not accepted by sub-item system
Email	No	Email format not supported as primary property for sub-items
Phone	No	Phone format not supported as primary property for sub-items

You can now identify and fix sub-item display problems by ensuring the target database uses a Title or Text property as its primary column. After applying the fix, test the relation by linking a new row in the parent database. For advanced setups, consider using a formula to combine multiple text properties into a single Title column, then set that formula as the primary property — but only if the formula output is a plain text string. That approach keeps sub-items working while showing dynamic labels.