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JDBC driver, SQL parser, and planner that generates logical plan. Test very simple statement that returns a single column that is a map; returns 5 rows.
Convert JSON result into an immutable tree of ordinary Java objects (List, Map, String, Double, Integer, Boolean). We use sorted maps, so that the tree is deterministic.
flatten first pass: out a new output field

doing everything but splitting out arrays into multiple records

multiplying, but not cloning properly

deep copy of data values, working flatten

cleanup

cleanup

drop working
Update logical plan to latest spec.  Fix existing ROPs to match new logical spec.  Update/add reference storage engine implementations.

fixes to make sql parser work with newer syntax
LeftJoin and RightJoin
Add Inner and Outerjoins
Skip join check if not able to be compared
Remove ProxyJoinedRecord