> For the complete documentation index, see [llms.txt](https://docs.fabricplan.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fabricplan.com/documentation/readme/powertable-sheets/how-tos/adding-columns-overview/add-visual-column/multi-select-relationship-column.md).
# Multi-select relationship column
A multi-select relationship column allows you to select one or more values from a related table for each record in the primary table. A **relation** table maintains the relationships between the primary and related tables, enabling a record to be associated with multiple related values.
By retrieving values directly from another table, it helps maintain data consistency, reduces manual data entry, and ensures that you choose only from valid entries. Multi-select relationship columns also make it simple to join records across tables that share one or more common columns.
In this article, you learn how to add a multi-select relationship column in the primary table and connect to records in a related table.
#### Prerequisites
Before creating a multi-select relationship column, make sure that the following tables exist in the database:
* The primary table.
* The related table (lookup table) containing the selectable list of values.
* A relation table that stores the relationships between the records of the primary and lookup tables.
{% hint style="info" %}
#### Note
If the required tables do not exist, create or import them to the database before configuring the multi-select relationship column.
{% endhint %}
You can import them using powertable from external sources such as Excel or CSV files. For more information, see [this section](/documentation/readme/powertable-sheets/how-tos/create-a-table-app-with-powertable-sheets.md).
### Add multi-select column
In the following example, you add a *Sales Rep* multi-select column to the *Products* table so you can assign one or more sales representatives to each product.
This column retrieves column values from the *Sales Representatives* table (lookup table) using the relationship information obtained from the *Rel\_SalesRep\_Products* table (relation table).
To add a multi-select column:
1. Select **Insert Column** > **Visual Column** > **Add Multi-Select Relationship Column**.
2. Enter a name for the column in the **Column Name**.
3. Enter the lookup table details. This is the table from which the list of values for each record will be retrieved. Use the dropdown menus to select the items listed below.
* Lookup table: *Sales Representatives*
* Lookup column: *First Name*
* Lookup Key: *Sales Rep Key*
4. Specify the **relation table**, the **reference column** that stores the lookup table key, and the **identifier columns** used to match records between the primary table and the lookup table. These mappings are used to establish and maintain the relationship between the tables.
Relation table details
This stores or updates the mapping between products and sales reps in the relationship table as we assign and unassign sales reps to the products in the app. Click **Save.**
### Review the multi-select relationship column
We have now successfully added a multi-select relationship column, which allows you to select and assign multiple sales representatives to each product.
Multi-select relationship column
After assigning, you can click **Save** and **Proceed** to save your changes to the database.
Save changes
The relation table is also simultaneously updated based on the selected values.
---
# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.
## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.
Perform an HTTP GET request on the current page URL with the `ask` query parameter:
```
GET https://docs.fabricplan.com/documentation/readme/powertable-sheets/how-tos/adding-columns-overview/add-visual-column/multi-select-relationship-column.md?ask=
```
The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.
Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.