Currently it's not well supported for CompareTupleFilter to have a child of CompareTupleFilter. However, in some cases, it's better to support it.
The (1=1) can be transformed to "true". And then this filter can be pushed down to hbase. Otherwise, the filter (colA = (1=1)) does not work in hbase.
And it may return incorrect results for the following SQL:
In the final result, all of the keys will become 'B'.