nvarchar

NVARCHAR is a data type used in many database systems to store variable-length Unicode character strings. The 'N' prefix signifies that the data type can store Unicode characters, which encompass a much wider range of characters than traditional single-byte character sets. This allows for the storage of text from various languages and symbols, including those with diacritics or characters found in non-Latin alphabets.

The term 'VARCHAR' indicates that the string is variable-length. This means that storage space is only allocated for the actual characters entered, plus a small overhead, rather than reserving a fixed amount of space regardless of the string's length. This can be more efficient in terms of storage when dealing with strings of varying sizes.

When declaring an NVARCHAR column, a maximum length is typically specified, such as NVARCHAR(50) or NVARCHAR(255). This sets an upper limit on the number of characters that can be stored in that column. The exact implementation and maximum lengths can vary between different database management systems like SQL Server, MySQL, PostgreSQL, and Oracle. Choosing the appropriate length is important for balancing storage efficiency and the potential data needs.