Two tables in our SQL Server DB equate to 500M rows and 350GB of data. Disk space is an issue where we keep backups and the time to execute backups is as well. We plan to truncate these 2 tables.
I understand that to reclaim the disk space, we'll need to shrink the DB after truncation, then do an index rebuild to fix fragmented indexes afterwards. But as we are not sure how long the rebuilds will take (we are spinning up a test server VM in Azure now to test), in the meantime we are looking for incremental gains. After just truncating (before shrink and rebuild), will the backup times and the resulting backup file size (after 7z compression) be reduced dramatically as a result?