Microsoft SQL Server 2012 Internals

Data compression

SQL Server provides the capability of data compression, a feature introduced in SQL Server 2008 and available in the Enterprise edition only. Compression can reduce the size of your tables by exploiting existing inefficiencies in the actual data. These inefficiencies can be grouped into two general categories.

• The first category relates to storage of individual data values when they are stored in columns defined using the maximum possible size. For example, a table might need to define a quantity column as int because occasionally you could be storing values larger than 32,767, which is the maximum smallint value. However, int columns always need 4 bytes, and if most of your quantity values are less than 100, those values could ...