DRILL-3151: Fix many ResultSetMetaData method return values.
Added ~unit test for ResultSetMetaData implementation.
Made getObject return classes available to implementation of getColumnClassName:
- Added SqlAccessor.getObjectClass() (to put that metadata right next to code
to which it corresponds rather than in far-away parallel code).
- Added similar AvaticaDrillSqlAccessor.getObjectClass().
- Changed DrillAccessorList.accessors from Accessor[] to
AvaticaDrillSqlAccessor[] for better access to JDBC getObject return class.
- Extracted return classes from accessors to pass to updateColumnMetaData.
Reworked some data type mapping and utilities:
- Added Added Types.getSqlTypeName(...).
- Renamed Types.getJdbcType(...) to getJdbcTypeCode(...)
- Replaced Types.isUnSigned with isJdbcSignedType.
- Fixed various bogus RPC-type XXX -> java.sql.Types.SMALLINT mappings.
- Removed DrillColumnMetaDataList.getJdbcTypeName.
- Moved getAvaticaType up (for bottom-up order).
- Revised DrillColumnMetaDataList.getAvaticaType(...).
MAIN:
- Updated updateColumnMetaData(...) to change many calculations of metadata
input to ColumnMetaData construction. [DrillColumnMetaDataList]
Updated other metadata tests per changes.
