If I’m not mistaken, this won’t work as the database DATE type cannot be stored as the string "infinity". The column would have to be a varchar and then you would have to perform date parsing in the where clause (and indexing by it would be poor as well). The best thing I can recommend is when the date is exactly equal to the highest and lowest values in the datetime, those are markers for infinity and negative infinity (looks like 4713 BC and 294276 AD for postgres). Try making your custom type use those values instead.
