I have a views block that displays related nodes based on tags. (See Entity Reference get nodes based on tags.) The comment links to the solution I found.
Now, I have to add another filter to the view.
Some of the related nodes have a date field (start and end date), and some do not. When I add a filter to exclude nodes where end dates have come and gone, no related nodes without the date field is shown.
How is it possible to filter out nodes where the end date is greater or equal to now on nodes with the date field, but still show nodes that do not have the date field?