# Aggregation - ordered list

The Ordered List aggregation is a variation of the existing List Distinct option. List Distinct returns a delimited list, ordered by the most frequently occurring values, together with the number of times each has occurred – see below:

## Using ordered list aggregation

The Ordered List aggregation function puts all transactions into order by the selected sequence variable and returns the information as a delimited list. For example:

1. Create a new data grid and add the **Surname**, **Region** and **Destination** variables.

   By default, the data grid will set itself to the lowest table level of the variables in use – here **Bookings filtered to Return all Bookings**, but override this and:
2. Right-click and set the table level to **People**.
3. Click on the icon, check the Apply Column Aggregation box and set the Grouping table to **People** and the Transactional table to **Bookings**.
4. Click on the **Edit Sequence Variable…** button and drag **Booking Date** onto the **Sequence by** drop-box.

   By default, the **List Distinct** function is applied to the Destination column. To amend this:
5. Right click on the **Destination** column header and select **Aggregate to People…**
6. Select **Ordered List** from the Function drop-down menu.
7. Rebuild the display.

   To verify the results and see the date of each booking:
8. Add the **Booking Date** variable to the Data Grid.

   As above:
9. Change the default List Distinct to the **Ordered List** function and rebuild.

> [!NOTE]
>
> The maximum output string length is 255 characters.

**See also**: [Column Aggregation](<https://help.apteco.com/en/faststats/visualisation/data-grid/display-column-aggregation/index.md>).