SQL Server 2014
SQL Server 2014 was released to manufacturing on March 18, 2014, and released to the general public on April 1, 2014. Until November 2013 there were two CTP revisions, CTP1 and CTP2. SQL Server 2014 provides a new in-memory capability for tables that can fit entirely in memory (also known as Hekaton). Whilst small tables may be entirely resident in memory in all versions of SQL Server, they also may reside on disk, so work is involved in reserving RAM, writing evicted pages to disk, loading new pages from disk, locking the pages in RAM while they are being operated on, and many other tasks. By treating a table as guaranteed to be entirely resident in memory much of the ‘plumbing’ of disk-based databases can be avoided.
For disk-based SQL Server applications, it also provides the SSD Buffer Pool Extension, which can improve performance by cache between DRAM and spinning media.
SQL Server 2014 also enhances the Always On (HADR) solution by increasing the readable secondaries count and sustaining read operations upon secondary-primary disconnections, and it provides new hybrid disaster recovery and backup solutions with Windows Azure, enabling customers to use existing skills with the on-premises version of SQL Server to take advantage of Microsoft’s global datacenters. In addition, it takes advantage of new Windows Server 2012 and Windows Server 2012 R2 capabilities for database application scalability in a physical or virtual environment.
Microsoft provides three versions of SQL Server 2014 for downloading: the one that runs on Microsoft Azure, the SQL Server 2014 CAB, and SQL Server 2014 ISO.
SQL Server 2014 SP1, consisting primarily of bugfixes, was released on May 15, 2015.