Saving Hive metastore on HDP by dumping

You must dump the Hive metastore metadata immediately before upgrading or migrating. Dumping the metastore data to a file is critical to prevent data loss.

On the node where the database you use for Hive Metastore resides, dump Hive Metastore metadata before upgrading/migrating to HDP.
For example, in MySQL, dump each database as follows:
```
mysqldump <hive_db_schema_name> > </path/to/dump_file>
```
In Postgres, dump each database as follows:
```
pg_dump --opt <metastore_db_name> > /path/to/dump_file
```
Proceed to upgrade/migrate HDP, assuming no Hive update, delete, or merge occurred after compaction; otherwise, repeat the compaction and Hive Metastore dump procedures, and then upgrade/migrate from HDP.