There is no other solution than re-factoring your code if you wish to upgrade to SQL2014. The example below demonstrates that setting the compatibility level to 2008 does not resolve this error. You will have to modify all your stored procedures and views.
ALTER DATABASE database_name SET COMPATIBILITY_LEVEL = 100
GO
--DOESNOT WORK IN 2012
DECLARE @ESTRecords TABLE
(
ESTime TIME(7) NOT NULL ,
ESTDate DATE NOT NULL ,
ESTDateTime AS ( CONVERT(DATETIME, ESTDate, ( 108 )) + ESTime )
PERSISTED
)
INSERT INTO @ESTRecords
( ESTime, ESTDate )
VALUES ( '12:00 PM', '12/31/2012' )
SELECT *
FROM @ESTRecords