In order to support UNICODE, special data types like NVARCHAR and NCHAR, were added in earlier versions of SQL Server. Originally, those data types used UCS-2 encoding, which support 65536 code points using 2 bytes. UTF-16 encoding was added to support 1114112 code points using 2 or 4 bytes.

Azure Database and SQL Server 2019 introduced new Supplementary Character "_UTF8" to support UTF-8 encoding using non-"National Character" Data types like CHAR and VARCHAR.

UTF-8 encoding provides full compatibility to other data types, to external applications, and to different Operating Systems. Using UTF-8 can reduce data size dramatically up to 50% and potentially improve performance accordingly.

In this session we will start with theory and best practice of textual data types and different types of encoding (ASCII, UCS-2, UTF-16, and UTF-8), and will dive to "SQL Server internals" behind the scenes.

* Note! The meeting fits developers, ‎Database administrators, and Architects. We'll review the theory (level 200) as well as the internals (level 400).