This CL includes: * Change the column metadata to a tree structure. * Refactor the segment_v2.ColumnReader and sgment_v2.ColumnWriter to support complex type. * Implements the reading and writing of array type.
This CL includes: * Change the column metadata to a tree structure. * Refactor the segment_v2.ColumnReader and sgment_v2.ColumnWriter to support complex type. * Implements the reading and writing of array type.