In-Memory OLTP: This allows users to create in-memory optimized online transaction processing (OLTP) tables in a standard relational database. It uses a combination of latch-free data structures and multi-version concurrency control (MVCC) to create a system where user processes can run without stalling or waiting. Stored procedures in memory-optimized tables are compiled to very efficient code, which maximizes run-time. This feature is only available in the 64-bit Enterprise Developer or Evaluator versions of SQL Server 2014.
Columnstore indexes: SQL Server 2014 introduces the xVelocity memory-optimized columnstore index, a new type of non-clustered index. It speeds up the processing time for common data warehouse queries. xVelocity columnstore indexes are based on Vertipaq in-memory data compression technology, which allows a large amount of data to be compressed in-memory. This means that queries require less I/O. Unlike SQL Server 2012, columnstore indexes in SQL Server 2014 can be updated.
Buffer pool extension: The extension provides integration of the Database Engine buffer pool with a non-volatile random access memory (solid state) drive. This increases random I/O throughput, reduces I/O latency, improves read performance and creates a caching architecture that can take advantage of low-cost drives.
IO resource governor enhancements: SQL Server 2014 provides two new settings for the Resource Governor. The Resource Governor is used to control the physical I/Os issued for user threads in a resource pool. The new settings are MAX_IOPS_PER_VOLUME and MIN_IOPS_PER_VOLUME. The settings are minimum and maximum physical I/O operations per second per disk volume for a resource pool. These can help predict physical I/O operations for a critical workload.
AlwaysOn Enhancements: In SQL Server 2014, AlwaysOn Availability Groups are integrated with Windows Azure virtual machines. This means that administrators can now add Windows Azure VMs as asynchronous Availability Group replicas. SQL Server 2014 also supports eight secondary replicas that are available for read workloads even when disconnected from the primary replica.
Windows Azure integrated back-up: Administrators can directly backup SQL Server databases on-premises to Windows Azure Storage. Administrators can also restore backups from Windows Azure Storage.
Security permissions: SQL Server 2014 has three new security permissions -- CONNECT ANY DATABASE, IMPERSONATE ANY LOGIN and SELECT ALL USER SECURABLES. These allow the database administrator to do his job without seeing the underlying user data.
Encryption for backups: SQL Server 2014 can encrypt data in the database during a backup operation.
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