commented [FLINK-3593][tableAPI] Fix failing DistinctITCase

commented [FLINK-3573] [table] Implement more String functions for Table API

commented [FLINK-3474]: Enable partial aggregate in Table API -- add new Aggregate interface which support partial aggregate -- implement SUM/COUNT/AVG/MIN/MAX aggregate functions implementation -- sorted-based runtime support this closes #1746

commented [FLINK-3564] [table] Implement distinct() for Table API This closes #1754

commented [FLINK-3567] Fix selection on grouping. Only grouping keys or aggregates allowed. This closes #1761

commented [FLINK-3498] Implement TRIM, SUBSTRING as reference design for Table API

commented [FLINK-3486] [tableAPI] Fix broken renaming of all fields.

commented [FLINK-3504] Fix join translation. Equality predicates may only reference fields. Catch Calcite planner exception and rethrow with additional error message This closes #1734

commented [FLINK-3537] Fix code gen for disjunctions. This closes #1733

commented [FLINK-3502] Add test case. Bug was resolved by a previous commit.