Found by Bingjie Miao
Due to false positives and Distinct scan rows eliminated
We should apply filter on indexScan or disable covering
|Covering FLATTEN_KEYS() on an array index generated incorrect results. This was because a modified version of the ANY clause was applied after the index which meant false positives were retained and Distinct scan rows were eliminated.
|The ANY filter is now applied on an index scan itself when covering an index scan with flatten keys.