*Description:* By pgsql 8.4 I have the following bug:
If the haystack array is null (for example by empty result of array_agg) by is contained by, and you use it with negation, the the result is false instead of true. *Reproduce:* The following query returns nothing, but it should return 1. *SELECT 1 FROM NOT(ARRAY[1] <@ NULL**); * *Workaround:* *SELECT 1 FROM (haystack IS NULL OR NOT(ARRAY[1] <@ **haystack**)); *
