The Unique ID is a required column in every dynamic feed, and is automatically available as a reporting dimension. (In Report Builder, the Unique ID dimension is called Dynamic Element Value ID.)
Each cell within the Unique ID column must be populated with a unique value. Advertisers can choose any unique value that makes sense for their strategy and feed setup (i.e. numbers, letters, product SKUs, etc.), but each Unique ID value should be associated to the same exact row of content throughout the duration of the campaign.
The Unique ID column is extremely important for reporting and optimization. It is used to track impressions and optimization associated to a particular iteration of content. Therefore, if there is a need to change content within an existing row in the feed, then this existing row should be given a new Unique ID value. Additionally, if you add a brand new row of content, the new row should also be given a new Unique ID value.
If the Unique ID is not used properly, there is no way to notice via previewing. The correct version will serve based on the targeting criteria, but optimization and reporting will be incorrect.
Review some examples of improper and proper Unique ID usage below.
Examples of Unique ID usageLet's take a look at some examples of Unique ID usage. We'll start with an example of improper usage of Unique ID to show how it affects reporting and learning for optimization.
Improper usage of Unique ID
Below is a simplified feed with two rows. So far, the following impressions have been served: 1,000 for Hats and 200 for Mugs.
| Unique ID | Placement ID | Product | Price |
|---|---|---|---|
| 1 | 11111 | Hats | $5.99 |
| 2 | 22222 | Mugs | $3.99 |
Let's add a row to the feed for a new product, Glasses. The impressions served are as follows: 200 for Hats; 300 for Mugs; and 100 for Glasses.
| Unique ID | Placement ID | Product | Price |
|---|---|---|---|
| 1 | 33333 | Glasses | $9.99 |
| 2 | 11111 | Hats | $5.99 |
| 3 | 22222 | Mugs | $3.99 |
If we pull a report now, we will see the following total impressions over the life of the campaign because impressions are always associated to the Unique ID value:
Hats (currently, Unique ID = 2) = 400 impressions
Mugs (currently, Unique ID = 3) = 300 impressions
Glasses (currently, Unique ID = 1) = 1,100 impressions
Since we initially associated Unique ID 1 with Hats and then used ID 1 for Glasses, we're receiving a very misleading report, indicating the Glasses row has received the most impressions. In reality, Glasses has only received 100 impressions over the lifetime of the campaign, but since we used an existing ID when we added the new row for Glasses, the impressions that were originally tracked under the ID are now being attributed to Glasses.
This causes similar issues with learning for optimization. As a result, reporting may show rows with higher impressions but lower CTRs, which seems counterintuitive. The issue really may be that the Unique ID has been used incorrectly, throwing off learning and therefore reporting.
Proper usage of Unique ID
Now, let's look at how the above feed should have been set up.
Below is the original example feed with two rows. So far, the following impressions have been served: 1,000 for Hats and 200 for Mugs.
| Unique ID | Placement ID | Product | Price |
|---|---|---|---|
| 1 | 11111 | Hats | $5.99 |
| 2 | 22222 | Mugs | $3.99 |
We add a row to the feed for a new product, Glasses. It does not matter where in the feed we add the new row, it only matters that the new row has a new Unique ID value. The impressions served are as follows: 200 for Hats; 300 for Mugs; and 100 for Glasses.
| Unique ID | Placement ID | Product | Price |
|---|---|---|---|
| 3 | 33333 | Glasses | $9.99 |
| 1 | 11111 | Hats | $5.99 |
| 2 | 22222 | Mugs | $3.99 |
If we pull a report now, we will see the following total impressions over the life of the campaign:
Hats = 1,200 impressions
Mugs = 500 impressions
Glasses = 100 impressions
These are the correct results! We have successfully used the Unique ID this time around, and the reporting and learning is reflecting that!
After uploading your feed to Studio in Step 2: Manage Data in the Dynamic workflow, select the name of the column designated as the Unique ID column in the ID drop-down.
When using product level remarketing, the column that contains the remarketing values can double as both the targeting column and the Unique ID column. When setting up the feed, the advertiser does not need to create a separate Unique ID column. In Step 2: Manage Data, the name of the remarketing column is selected in the ID dropdown. This saves time for advertisers and decreases the complexity of the feed.
This setup will only work if each remarketing value is a single, unique value. There cannot be duplicate values, and there cannot be multiple values in the same cell within this column.