Custom columns FAQ

Custom columns can only be saved if they include a valid name, a valid formula, and a data format that matches the formula.

If you can’t save your custom column, check for a red error message below the formula area or under the column name. This message will tell you why the custom column can’t be saved.

If the formula is invalid due to a syntax error, one or more red underlines will appear under part of the formula. These underlines provide an approximate location in the formula where the error was detected. You might need to modify a part of the formula that isn't above the underline to fix the error (for example, adding another parentheses at the beginning or end of the formula to fix a mismatched parentheses error).

Common reasons why a formula might be invalid include:

• Mismatched data types: Every column, constant and function has a data type (number, text, true/false or date). Ensure that you’re combining columns, constants and functions in compatible ways. For example, the length function only accepts text values, so length(Clicks) is invalid because clicks is a number. Check the column list, function list and the operator list for their data types.
• Missing operator: An operator must be placed between each column, constant, function and parenthetical expression. For example, 2(Impr + Clicks) is invalid because an operator (such as *) is missing after the number.
• Mismatched parentheses: Check that every open and closing parenthesis has a corresponding parenthesis of the opposite type placed correctly. For example, (56 * round(Clicks)) + Clicks) is invalid because there is no open parenthesis that corresponds correctly with the last parenthesis after the clicks column.
• Misspellings: Check the list of columns, filters and functions in custom columns for the correct spellings of common custom column content.
• Misuse of double quotes: Ensure that double quotes are used correctly. Numbers, standard columns and true/false values should generally not be surrounded by double quotes because double quotes will cause the value to become text. For example, ("Clicks" > 4) = "true" would be invalid. Instead, this formula should be written as (Clicks > 4) = true. Only custom column references, certain filters and text constants use double quotes.
• Missing order of operations: Check that you have parentheses surrounding the calculations that should happen first. For example, Clicks * 2 > 10 may not be saved because it may attempt to calculate the > comparison first, then multiply second, which isn't valid. Instead, wrap the first operation in parentheses to save the formula: (Clicks * 2) > 10.
• Column names should be shown in an oval (visual mode only): When you add a column to your formula while in visual mode (default), you must select it from the drop-down that appears while typing its name to convert it to an oval. If you have columns in your formula that aren't represented by an oval, try inserting the column using the + Column button.

When editing an existing custom column, there are two cases where you may be prompted to save your custom column as a new custom column instead of updating the existing custom column. In these cases, you’ll also see an option to 'Save as new column'. If you select this option, your edited formula will be copied into a new custom column and you can save the custom column under a new name.

'You can’t save this change because the formula content no longer matches the column format.'

This occurs when a formula is changed so that it no longer matches the selected data format for the formula. The data format of a custom column may not be changed after the custom column is created. For example, if your formula is Clicks / Impr and your data format is per cent, then you modify your formula to Clicks > Impr, you can’t save this change because it would change the data format to True/False.

'You can't save this change because it could result in errors for reports that might be using this custom column.'

This occurs when you add or remove certain columns or other custom columns from the formula that would impact the way the custom column is displayed in charts and in summary rows. For example, if the formula contains only the Clicks and Conversions columns, but you edit the formula to also include the Campaign name column (which can’t be displayed in charts), you'll see this error. You may see this error even if your custom column isn't currently used in any tables, charts or reports.

You can copy a formula when in text mode, then paste it into a new custom column when in text mode:

1. Select the pencil icon beside the custom column that you want to copy/duplicate.
2. Change to text mode.
3. Highlight the entire formula’s text.
4. Copy the formula (Ctrl+C or Cmd+C).
5. Select Cancel to close the formula editor.
6. Select + custom column to create the new custom column.
7. Change to text mode.
8. Paste the formula (Ctrl+V or Cmd+V) into the formula area, and make any desired changes.
9. Provide a unique name for the new custom column.
10. Select the desired data format.
11. Save the new custom column.
12. (Optional) You can remove the previous custom column if it’s no longer needed.

Custom columns display dashes in the table when a formula doesn’t have any valid value to show in a row. Common reasons include:

• A dependency is also empty: If one of the columns that's included in the custom column’s formula is displaying a dash in a row, then the custom column will also display a dash in that row. You can check the value of each column included in the formula by also adding it to the table.
• Incompatible filters: Some columns and filters are incompatible in certain tables, even if you can save a custom column with the combination. For example, adding a conversion source filter on a Clicks column will make the custom column show a dash because Clicks can’t be filtered by conversion source.
• Calculation error: If the formula could not be computed due to a calculation error, it will show a dash. For example, if you wrote a formula that multiplies two extremely large numbers, it could result in a calculation error.
• Summary row: Dashes may appear in the summary rows for custom columns under certain conditions.

A custom column can’t be added to a table if the custom column’s formula includes columns or filters that aren’t available for that table. Similarly, if the formula includes another custom column that can't be added to the table, the custom column can’t be added to the table either.

You can add the custom column to a different table that has all of the columns and filters used in the formula available, or you can modify the custom column’s formula to remove the columns or filters that aren't available on the current table.

• There may not be more than 1,000 custom columns owned by one account.
• Custom column formulas may not be longer than 10,000 characters when viewed in text mode
• Up to two different filter types (e.g. Device, Network, etc.) may be added to a formula across all columns in the formula. There's no limit on the number of values allowed in each filter.
• A custom column may not reference any more than five other custom columns directly in its formula
• References of custom columns to one another may not create a chain of references longer than four. For example, if column A referenced column B, which referenced column C, which referenced column D, then column D may not reference any other custom column because this would increase the chain length to five. Likewise, in this scenario, no other custom column may reference column A, since that would also increase the chain length to five.
• Custom column references may not create a cyclical chain. For example, if column A referenced column B, which referenced column C, then column C may not reference column A or column B.

To create a custom column that shows the value of certain conversion actions, follow these steps:

1. Create a new custom column.
   1. In the top right-hand corner of a table, click the columns icon , then select Modify columns.
   2. Click + custom column in the top right.
2. Start with a base conversion metric (for example, use 'All conversions' if you’re interested in the count of conversions).
   1. Click the + column button and expand the Conversions section.
   2. Select the base conversion metric (for example, 'All conversions' for the number of conversions).
3. Select filters to limit the selected metric to specific conversion actions.
   1. Click the grey oval in the formula area that represents the column that was just added (if it’s not blue).
   2. In the filter panel on the side, expand the Conversion actions section.
   3. Select one or more conversion actions to limit the base metric to only the selected actions. If no actions are selected, the metric is unfiltered.
4. Name the custom column and click Save.

Once a custom column is saved for the first time, its 'data format' may not be changed.

If you're editing an existing custom column and make changes to the formula that change the formula output between a numeric value, a text value, a true/false value and a date value, you'll be automatically prompted to save the changes as a new custom column.

If you want to change the 'data format' between 'Number', 'Per cent' and 'Currency', you can copy the current formula to a new custom column.

Whenever text is used in a formula, it is surrounded by double quotes. If you want to include the double quote character in your text, you can 'escape' the character by placing two double quotes back-to-back. This applies anywhere double quotes are used in formulas, including text constants, references to other custom columns and filter values.

For example, if you wanted to display My “Fast” Flowers as the value of a custom column, you would write "My ""Fast"" Flowers" as the formula.

The value of custom columns in summary rows are calculated across the row horizontally.

For example, if Custom Column A is Clicks > 10 and Custom Column B is CTR * 2, a table might look like following example, where the third row is the summary row:

Some custom columns may not have any value in summary rows (or may have a dash displayed), even though it may have a value in other rows. Reasons can include:

• The custom column’s 'data format' is 'Text', 'True/False' or 'Date'.
• The custom column’s formula includes a column that doesn’t have an addable value (like Campaign name), or it includes another custom column that includes a non-addable column in its formula.

Some custom columns can’t be used in charts. Reasons can include:

• The custom column’s 'data format' is 'Text', 'True/False' or 'Date'.
• The custom column’s formula includes a column that doesn’t have an addable value (like Campaign name), or it includes another custom column that includes a non-addable column in its formula.

In visual mode, column names, filter names and filter values are localised to the same language as the rest of Google Ads. However, function names are the same regardless of your language. See the function list for a list of functions.

In text mode, all column names, filter names, filter values and functions are the same regardless of your language preference. The names used in text mode are similar to the English names for each item, but are modified to not include spaces or special characters. See the column list, filter list and function list for a full list of allowed values.

In both modes, use a period as the decimal separator. For example, a quantity of five-and-a-half would be 5.5 instead of 5,5. A thousands separator isn't used in formulas.

Additionally, columns that may be a fixed set of text values (like the Campaign status column) will always return English text (such as Enabled) when used in a formula. See the column list for the values that may be returned.