@Override
public ColumnMetadata getColumnMetadata(TableHandle tableHandle, ColumnHandle columnHandle)
{
SchemaTableName tableName = getTableName(tableHandle);
checkArgument(columnHandle instanceof TpchColumnHandle, "columnHandle is not an instance of TpchColumnHandle");
TpchColumnHandle tpchColumnHandle = (TpchColumnHandle) columnHandle;
int columnIndex = tpchColumnHandle.getFieldIndex();
return tables.get(tableName).getColumns().get(columnIndex);
}