Lookup custom fields allow you to import data from records in other projects, creating one-way visibility. While Reference custom fields establish connections across projects, Lookups use those connections to surface selected data.
Lookup custom fields are always read-only and are connected to a specific Reference custom field. When a user selects one or more records using a Reference custom field, the Lookup custom field will show data from those records.
Lookups can show data such as:
- Created at: When the referenced record was created.
- Updated at: The last date and time when the referenced record was updated in any way.
- Due Date: The reference record's start/due date and time.
- Description: The description field of the referenced record.
- List: Shows the list that the referenced record belongs to.
- Tag: Any tags that the referenced record is tagged with.
- Assignee: Any assignees to the referenced record.
- Any Custom Field: Any supported custom field from the referenced record.
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Lookup fields have many options
You can create custom fields to store and reference data across multiple different projects. These custom fields are called "Lookup" fields.
Let's consider three projects:
- Project A
- Project B
- Project C
Suppose Project B contains some critical information or resources that are relevant to both Project A and Project C.
Instead of duplicating the information from Project B into Project A and Project C, follow these steps:
- In Project A, create a "Reference" custom field to establish a connection with the relevant record from Project B.
- This Reference custom field allows you to select and link to the specific record in Project B that you want to reference and lookup.
- Once the Reference field is set up in Project A, create a "Lookup" custom field in Project C.
- This Lookup custom field will be connected to the Reference custom field in Project A.
- When you select records using the Reference custom field in Project A, the Lookup custom field in Project C will automatically display relevant data from those referenced records in Project B.
- You don't need to directly link Project C to Project B.
- Project C can leverage the connection established between Project A and Project B through the Reference and Lookup fields.
- Any changes or updates made to the relevant records in Project B will automatically reflect in the Lookup custom field data displayed in Project C.
- No need for manual updates or duplication of information across projects.