SQL Server 2012 vs 2014
There are lots of new features added in SQL Server 2014 to improve query performance, main difference between SQL Server 2012 and SQL Server 2014 are listed in this article.
* SQL Server 2012 supports upto 64 GB RAM, SQL Server 2014 supports 4 TB RAM.
* SQL Server 2012 supports upto 4 replicas in AlwaysOn technology whereas SQL Server 2014 supports upto 8 replicas.
* SQL Server 2012 mainstream support is ending in 2017 and SQL Server 2014 will be ending in 2019.
* SQL Server 2012 dosen’t not use In-Memory OLTP feature, In- Memory OLTP feature added in sql server 2014 which means you can keep most used table in memory to improve query performance (lock free and latch free).
* SQL Server 2012 supports clustered columnstore indexes with datatype limitation, SQL server 2014 supports both clustered and Non clustered cloumnstore indexes
New added permisison in SQL Server 2014
CONNECT ANY DATABASE -> You can login to any database using this permission on existing and future without providing individual permisison on each database.
SELECT ALL USER SCURABLES -> It is allow you to execute select query against all tables of all user database, this permisison is useful incase you need to provide select to common user having access to all tables of all database.
IMPERSONATE ANY LOGINS -> This allows a login to impersonate any other login, without having sysadmin permission.