Implementation of SoundEx function is changed in SQL Server 2012, described here. For an example, the result of SOUNDEX(‘Csomorova’) in SQL Server 2012 is C561 whereas the result of it from SQL Server 2008 is C256.
It does not seem very significant to our life. But it gives you surprise when this function is used for a calculated column where the value of it is persisted in the index. The indexes containing this column will be disabled automatically after restoring an SQL Server 2008 database to SQL Server 2012. Here is the result
RESTORE DATABASE successfully processed 0 pages in 2.094 seconds (0.000 MB/sec). Warning: The index "PK_blablaView" on "blaSchema"."blablaView" was disabled because the implementation of "soundex" have changed. Warning: Clustered index 'PK_blaView' on view 'blaView' referencing table 'blaTable' was disabled as a result of disabling the index 'PK__blaTable'. Warning: The index "PK__blaTable" on "blaSchema"."blaTable" was disabled because the implementation of "soundex" have changed.
The solution is to rebuild indexes after restore.
Changed SoundEx Disables Index While Upgrading to SQL 2012