SQL Server Editions
There are several edition of SQL Server. Each Edition is differing in features, hardware, and cost.
Enterprise Edition : SQL Server 2012 Enterprise Edition supports 160 physical processors. It support all advanced availability features (e.g., table partitioning, data compression, creating and managing a SQL Server cluster). SQL Server 2012 manages thousands of connections. It includes both the core database engine and add-on services, with a range of tools for. It can manage databases as large as 524 petabytes and address 2 terabytes of memory.
Developer Edition: The Developer Edition is the same as the Enterprise Edition, but it’s licensed only for development and testing. It can be easily upgraded to Enterprise without reinstallation. This edition is available to download by students free of charge as a part of Microsoft's Dream Spark program.
Standard Edition: SQL Server Standard edition includes the core database engine, along with the stand-alone services. It supports fewer active instances (number of nodes in a cluster) and does not include some high-availability functions such as hot-add memory (allowing memory to be added while the server is still running), and parallel indexes. It is a good choice when advanced functions (such as data compression, compressed backups, indexed views, etc.) are not required for the business.
Standard edition is an affordable option for small and medium-sized organizations. ItIncludes the core functionality needed for non-mission-critical e-commerce, data warehousing, and line-of-business solutions.
Workgroup Edition: it is suitable for smaller departments. It supports systems up to 2 CPU and 4 GB RAM. It has features Import/Export, Limited replication publishing, clustering Back-up, log shipping, basic reporting. The key feature missing from Workgroup Edition is Integration Services. This edition has been retired in SQL Server 2012
Web Edition: As the name implies, the Web Edition, new for SQL Server 2008 is licensed for hosting websites. It supports 4 CPU and OS maximum of memory. Database size in web edition is not limited.
Express: SQL Server Express Edition is free edition of SQL Server. It includes the core database engine. While there are no limitations on the number of databases or users supported, it is limited to using one processor, 1 GB memory and 10 GB database files (4 GB database files prior to SQL Server Express 2008 R2).
Compact: It is free embedded database for mobile application development. The maximum size of the database is 4 GB. The SQL CE engine is based on SQL Mobile (initially designed for use with hand-held devices) and does not share the same binaries. Due to its small size it supports a subset of the standard data types, does not support stored procedures or Views or multiple-statement batches (among other limitations). It is limited to 4 GB maximum database.
SQL Server Analysis Services and SQL Server Integration Services are included only in Enterprise and Standard Edition. SQL Server Reporting Services is also very limited in the free editions.