Character Data Types
Character data types are strings of ASCII characters. Upper and lower case alphabetic characters are accepted literally. There are two fixed-length character data types, char and c, and two variable-length character data types: varchar and text.
The maximum row length in a table is 2008 bytes. Therefore, the maximum length of a character column is 2008 minus any additional space requirements. Additional space requirements for character columns are as follows:
• varchar columns require two additional bytes to store a length specifier
• nullable char and varchar columns require one additional byte to store a null indicator