SQL Server: String (character) datatype

Non-Unicode

1. char(n) : Fixed-length string with Maximum 8,000 characters


2. varchar(n) : Variable-length string with Maximum 8,000 characters


3. varchar(max) : Variable-length string with Maximum 1,073,741,824 characters


4. Text : Variable-length string with Maximum 2GB of text data or maximum length of 2^31 - 1 characters

Unicode

1. nchar(n) : Fixed-length Unicode data with Maximum 4,000 characters.


2. nvarchar(n) : Variable-length Unicode data with Maximum 4,000 characters.


3. nvarchar(max): Variable-length Unicode data with Maximum 536,870,912 characters.


4. ntext : Variable-length Unicode data. Maximum 2GB of text data or a maximum length of 2^30 - 1 characters