When we launched Home a few weeks ago, you clamored for us to add support for derived columns, especially for the Error field.
We listened and you can now configure your dataset to use a derived column in the Error field.
To configure this, first create a derived column in your dataset settings page. Then, click on the Honeycomb logo to navigate to Home, then click Configure. From there, you can choose your new derived column from the drop-down menu beside the Error name.
We calculate the Error Rate in the graph on home by calculating the average of a custom derived column. This looks like
IF(BOOL(<Your-derived-column-here>), 100, 0).
You can read more about derived columns on our docs page.