SQL Azure - Why is database size is much smaller when export and import to another database

Question

Currently my SQL Azure database size is 8GB. When I export the database to a bacpac file, and then import the bacpac file to a new SQL Azure database, the size of the new database is around 2.5 GB

Thats a huge difference in the sizes for the same data.

Anybody knows why this could be happening?

(I'm using the automated backup feature in the web based Azure admin area at manage.windowsazure.com. And I use the import feature in the same admin area to import the newly created bacpac to a new database)

Thanks

Answer 1

Backup would not contain as much log information. As well, fragmentation could have made the database grow in size and backup/restore defragmented it.