Using Binary Collations

The following considerations will help you to decide whether old or new binary collations are appropriate for your Microsoft SQL Server implementation. Support for both BIN and BIN2 collations will continue in future SQL Server releases.

Binary collations sort data based on the sequence of coded values defined by the locale and data type. A binary collation in SQL Server defines the language locale and the ANSI code page to be used, enforcing a binary sort order. Binary collations are useful in achieving improved application performance due to their relative simplicity. For non-Unicode data types, data comparisons are based on the code points defined in the ANSI code page. For Unicode data types, data comparisons are based on the Unicode code points. For binary collations on Unicode data types, the locale is not considered in data sorts. For example, Latin_1_General_BIN and Japanese_BIN yield identical sorting results when used on Unicode data.

Previous binary collations in SQL Server performed an incomplete code-point-to-code-point comparison for Unicode data. Older SQL Server binary collations compared the first character as WCHAR, followed by a byte-by-byte comparison. For backward compatibility reasons, existing binary collation semantics will not be changed.

Guidelines for Using Binary Collations

If your Microsoft SQL Server 2005 applications interact with older versions of SQL Server that use binary collations, continue to use binary. Binary collations may be a more suitable choice for mixed environments.

Guidelines for Using BIN2 Collations

Binary collations in this release of SQL Server include a new set of pure code-point comparison collations. Customers can choose to migrate to the new binary collations to take advantage of true code-point comparisons, and they should utilize the new binary collations for development of new applications. The new BIN2 suffix identifies collation names that implement the new code-point collation semantics. In addition, a new comparison flag is added corresponding to BIN2 for the new binary sort. Advantages include simpler application development and clearer semantics.

See Also


Collation Options and International Support
Collation Settings in Setup

Help and Information

Getting SQL Server 2005 Assistance