Restoring database between different version of SQL Server (SoftwareVersionBuild)
Migrating a database specifically from 2008 R2 SP2 to 2008 R2 SP1 will be fine*.

Migrating up or down service pack levels on the same SQL Server version is generally OK, because the internal database version number usually does not change.

There have been a couple of exceptions to this general rule. The one that might interest you concerns databases where support for 15,000 partitions has been enabled (changing the internal database version). If this scenario might apply to you, download and review the SQL Server Technical Article below:

Support for 15,000 Partitions in SQL Server 2008 SP2 and SQL Server 2008 R2 SP1.

Even so, going directly from a 2008 R2 SP2 instance to SP1 should not present any problems. Always have verified (restored and DBCC-checked) backups just in case.



* Caveat: If the SP2 database had support for 15,000 partitions enabled, it would not be accessible when restored to R2 RTM as an intermediate step. Applying SP1 would then resolve this. Good to know to avoid panic at the RTM stage :)