Currently when a table is altered, if any of below conditions is true, HMS would try to update column statistics for the table:
- database name is changed
- table name is changed
- old columns and new columns are not the same
As a result, when a column is added to a table, Hive also tries to update column statistics, which is not necessary. We can loose the last condition by checking whether all existing columns are changed or not. If not, we don't have to update stats info.