Views filter criteria groups OR not working?

Question

I have a view with FILTER CRITERIA set. I have three groups, each joined by ANDs, with the criteria within each group ORed. The final group are two taxonomy terms, meaning I want my query to return nodes that have one term or the other. No node will have both of the tags set.

However, when I see the SQL in the preview, the terms seem are connected by a AND.

WHERE (((node__field_event_categories.field_event_categories_target_id = '434')) AND ((node__field_event_categories2.field_event_categories_target_id = '212'))) AND ((taxonomy_index.status = '1') AND (((DATE_FORMAT((node__field_date_range.field_date_range_value + INTERVAL -14400 SECOND), '%Y-%m-%d\T%H:%i:%s') >= DATE_FORMAT(('2018-10-22T04:00:00' + INTERVAL -14400 SECOND), '%Y-%m-%d\T%H:%i:%s'))) OR ((DATE_FORMAT((node__field_date_range.field_date_range_end_value + INTERVAL -14400 SECOND), '%Y-%m-%d\T%H:%i:%s') >= DATE_FORMAT(('2018-10-22T04:00:00' + INTERVAL -14400 SECOND), '%Y-%m-%d\T%H:%i:%s')))))

This causes my query not to return any results.

I've tried removing each tid, one by one, and when one is missing I get results. So I'm thinking I should get both sets of results when they are set to OR.

To make sure I was reading the SQL correctly, I ran it through a pretty-printer:

To double check, I exported the views config, to see what the yaml said about the WHERE clause, and it all seems to be OR within the groups:

I even re-imported the configuration from this yaml, but I still get the same results.

How can I get my taxonomy criteria to function using OR?

Edit In the course of troubleshooting, I tried to simplify the filter criteria. I removed everything, all groups and criteria. This is what I have now:

This is Drupal 8.6.2. We just updated, so I'm wondering if this is a new bug.

Answer 1

This answer on a related (perhaps duplicate?) issue provided settings that got the display working for me.

First, on each filter criteria, check "Reduce Duplicates".

EDIT Actually, the answer I linked says to uncheck the "DISTINCT" in the Advanced settings for the query. However, when I did that, I got duplicates. I unchecked it, and I got the right number of results. So that second step may not be necessary for you.