1. let AggStateType extends Type 2. remove useless interface isFixedLengthType and supportsTablePartitioning 3. let MapType implement interface isSupported 4. let VariantType extends ScalarType
1. let AggStateType extends Type 2. remove useless interface isFixedLengthType and supportsTablePartitioning 3. let MapType implement interface isSupported 4. let VariantType extends ScalarType