Merging data feeds enables you to:

• Add columns of data to a data feed from one or more other data feeds - without having to manually write formulas.
• Add clarity by aligning columns that contain related data.

This article includes:

• When to merge data feeds
• Before merging data feeds
• How to merge data feeds
• Identifying your merged data
• Removing merged columns
• What to do if any of your data feeds change
• Editing a merged (secondary) data feed

When to merge data feeds

Merging data feeds enables you to bring your information together. This means you can consolidate complementary data feeds (provided they share at least one column in common) in order to create a data feed that provides a more complete version of your data and is easier for users to understand.

Here are some examples of when to merge data:

Simplifying by associating related data
You can add clarity to your data by associating complicated or technical data with more user friendly terms from a different data feed. For example, let’s say Data Feed A contains a list of sales data by country, but each country is only represented by an id number, not by a name. If Data Feed B contains both the country ids and the corresponding country names, you could merge the country names column from Data Feed B into Data Feed A, making the sales data easier to consume and understand at a glance.

Adding context and dimensions to your data
Merging data feeds can help you enrich your data. For example, let’s say you have sales by country in a data feed and you also want to show the sales regions those countries are located in (with multiple countries in each region). You could merge your data feed with another data feed that has the same list of countries with their corresponding regions. Now you can build a metric that has both region and country as dimensions, giving you more options for displaying and breaking down your data.

Before merging data feeds

Before merging data feeds, consider the following:

• Any data feed can have up to four data feeds merged into it.
• The total combined size of your merged data feed cannot exceed the data feed size limit for your account plus 3 MB. By default, the maximum size limit for a data feed is 10 MB and the maximum merged data feed size is 13 MB.
• Nesting of merged data feeds is not supported. You cannot select data feeds that already contain columns that have been merged from other data feeds.
  

How do I merge data feeds?

Follow these steps to create a merged data feed.

Step 1. Select the base data feed.

Click Data Feeds in the left navigation sidebar to open your list of data feeds. Select the data feed you want to use as a base. Click the Edit button and then click the Merge data button.

Step 2. Choose a data feed to merge

In the Merge data pane, select a data feed that has at least one column with data in common with a column in your base data feed (note that the columns don’t have to have the same column name). Once you have selected your data feed, click Next.

Step 3. Align your data feeds

Identify a column in the base data feed and a column in the secondary data feed that contains the same data in order to align the two. This is your join key. The join key columns must be of the same data type (numeric or text-based). The column from the second data feed should not contain repeating values (if it does, only the first value will be used). Your list of columns displays the column heading and type of data to help you make your selection. Once you have selected your columns, click Next.

Notes:

• If there are no matching values in the aligning columns (the join keys), the added columns from the second data feed will be blank. Only rows with a common value will have data in the added columns.
• If you select a data feed that does not align with your base data feed, the added columns will be empty.
• Columns with the Duration format type cannot act as join keys.

Step 4. Add columns

Once you’ve aligned your data, you can select the columns from the secondary data feed that you want to add to your base data feed. After selecting the desired columns, click Merge.

Step 5. Edit and save your merged data feed

Newly merged columns are added to the right of the base data feed. You can edit the merged column names, data types, and properties, but you will not be able to access the formula bar from here. Learn how to edit the formulas for these columns. You can modify the columns of the base data feed just as you would for a single data feed. To learn more, see Editing data feeds. When you’re happy with the merged data feed, click Save data feed.

Watch this brief video tutorial for an example of merging (joining) data feeds:

Identifying your merged data

To find out which data feeds were used to create a merged data feed, open the data feed and click the Edit button. You can view and edit the connections between merged data feeds using the merge map which displays under Merged Data. Clicking the 3-dot menu for a merged data feed in the merge map enables you to edit or delete the merge. You can also click the + button to add another data feed.

Depending on the order in which you merged new columns with your base data feed, the data feeds and their associated column headings will display one of the following colours:

Colour	Indication
	Original data feed
	1st merged data feed
	2nd merged data feed
	3rd merged data feed
	4th merged data feed

The names of each data feed you merge are displayed in the merge map under the heading Merged Data (below the toolbar) so you can easily associate each column with its source.

Removing merged columns

You may remove columns individually or delete the merge action to remove all columns from a particular data feed at once.

To remove columns individually:

1. Click the column you want to delete.
2. Click the Remove column button in the toolbar.
   Note: You can also remove a column using its drop-down arrow button.

To remove all columns for a particular merged data feed all at once:

1. Click the Merge data button to open the merge data pane.
2. From the merge map, click the three-dot menu for the merged data you want to remove.
3. Click Delete merge.
   

What to do if any of your data feeds change

If one or more of the data feeds you used to create your merged data feed changes, you may notice that some of your columns display as empty. The most common reasons for this are:

• Your join key no longer exists as a column
• The column you used as a join key is no longer valid (for example, because its formula was edited)
• At least one merged data feed has been deleted

If your data feed contains errors, your metrics may not display correctly. You can correct these errors by doing one of the following:

If your join key no longer exists as a column or is no longer valid:

1. Click the Merge data button to open the Merged Data pane.
2. Click the three-dot menu of the affected merged data feed in the merge map.
3. Click Edit merge.
4. Select a new pair of matching columns to align the two data feeds.
5. Click Apply.

If at least one merged data feed has been deleted:

1. Click the Merge data button to open the Merged Data pane.
2. Click the three-dot menu of the affected merged data feed in the merge map.
3. Click Delete merge.
4. If you are able to replace your deleted data feed, you can go through the merge procedure again.

Note: If a data feed is being used for metrics, new formulas will be applied to the metrics going forward, but the previously stored data will not be changed. Go here for more information on deleting and reimporting your metric data.

Editing a merged (secondary) data feed

After creating a merged data feed, you can use the formula bar to edit columns from your base data feed. However, if you want to edit columns that were brought into the merged data feed from secondary data feeds, you need to go to and edit the secondary data feed.

If you try to open the formula bar to edit a column that was added to your data feed using the  Merge data button, the formula bar will not display. Instead, you’ll see the message “This column is from” followed by a hyperlink to the secondary data feed from which the columns originated.

To edit columns that were added to your base data feed using the Merge data button:

1. Open the original (secondary) data feed and click the Edit button.
2. Modify columns using the formula bar as usual. When you save your changes, they’ll also display in the merged data feed.

Learn more about editing data feeds using formulas.

Note: Variables and formula references are not currently supported when editing a data feed.

Learn more

• Merging data feeds: Additional options