Last tested: Oct 7, 2019
Add the parameter full_suggestions: yes
to the dimension
The recommended strategy for handling nested fields in BigQuery is to create separate views for the nested fields and join them to the original table in the explore. The default full_suggestions: no
causes Looker to attempt to query a nested field as a standalone table, resulting in suggestion query failures. The nested field view only makes sense in the context of the explore, including the joins that unnest the fields, so it is necessary to manually set full_suggestions: yes
to override the default and run the suggestion query against the full explore.
This content is subject to limited support.
The process to figuring out that issue only happening with nested fields is with the help of this 6th point in this article https://help.looker.com/hc/en-us/articles/360058714853-Troubleshooting-Common-Filter-Suggestion-Issu...
Good one though!