If n is not specified when using the CAST and CONVERT functions, the default length is 30. When n is not specified in a data definition or variable declaration, the default length is 1. For more information about Unicode storage and character ranges, see Storage differences between UTF-8 and UTF-16. For example, in a column defined as char(10), the database engine can store 10 characters using single-byte encoding (Unicode range 0 to 127), but less than 10 characters when using multibyte encoding (Unicode range 128 to 1114111). However, for multibyte encodings such as UTF-8, higher Unicode ranges (128 to 1114111) result in one character using two or more bytes. The misconception happens because when using single-byte encoding, the storage size of char and varchar is n bytes and the number of characters is also n. This is similar to the definition of nchar(n) and nvarchar(n). n never defines numbers of characters that can be stored. However, in char(n) and varchar(n), the n defines the string length in bytes (0 to 8000). See full list on A common misconception is to think that with char(n) and varchar(n) the n defines the number of characters. For more information about character sets, see Single Byte and Multi Byte Character Sets. The ISO synonyms for varchar are charvaring or character varying. For multibyte encoding character sets, the storage size is still n bytes + 2 bytes, but the number of characters that can be stored can be smaller than n. For single-byte encoding character sets such as Latin, the storage size is n bytes + 2 bytes and the number of characters that can be stored is also n. Use n to define the string size in bytes and can be a value from 1 to 8000 or use max to indicate a column limit size up to a maximum storage of 2^31-1 bytes (2 GB). varchar ( n | max ) Variable-size string data. For multibyte encoding character sets, the storage size is still n bytes, but the number of characters that can be stored can be smaller than n. For single-byte encoding character sets such as Latin, the storage size is n bytes and the number of characters that can be stored is also n. n defines the string size in bytes and must be a value from 1 to 8000. See full list on char ( n ) Fixed-size string data. If a non-UTF-8 collation is specified, these data types store only a subset of characters supported by the corresponding code page of that collation. Starting with SQL Server 2019 (15.x) when using a UTF-8 enabled collection, these data types store the full range of Unicode character data and use the UTF-8 character encoding. › en-us › sqlchar and varchar (Transact-SQL) – SQL Server | Microsoft Learn › en-us › sql CachedOverview Arguments Comments Convert Character DataExamples See Also Applies to SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW) SQL Endpoint in Microsoft Fabric Warehouse in Microsoft Fabric Character data types either fixed-size char or variable-size varchar. –Ĭhar and varchar (Transact-SQL) – SQL Server | Microsoft Learn If you are programming in TI-Basic, 2 characters is too long since it only supports 1 character variable names. How long is too long for a variable name? – Stack overflowĭepends on the language.
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