I am indexing a document with an expiration date field that I use as a filter when querying for search results.
A document can either have a date or not, and I'm looking to filter by documents whose expiration is greater than today (i.e., in the future). When there is no expiration date for a document, what should I put as the value for the expiration date in the index? I was thinking something like '9999-12-31' (December 31, 9999) but that is really ugly. There are only gt, gte, lt and lte options on the range filter.
I was thinking of storing null in the field, but am having trouble with OR/AND'ing multiple filters because the expiration date must be in the future OR non-existent AND must match other parameters.