Character Types
The Character types allow you to store alphanumeric data, represent words and text, and manipulate the character strings.
CHAR
You use the CHAR datatype to store the fixed-length character data. How the data is shown internally depends on the database character set. The CHAR datatype takes an optional parameter that specifies a maximum length of up to 32767 bytes. The syntax is shown below:
CHAR[(maximum_length)]
You cannot use a variable or constant to specify the maximum length; you should use an integer literal in the range 1 to 32767.
If you do not specify the maximum length, it defaults to 1. Keep in mind; you specify the maximum length in bytes, not characters. Therefore, if a CHAR (n) variable stores multi-byte characters, its maximum length is less than n characters.
CHAR Subtype
The CHAR subtype of CHARACTER has the same range of values as its base type. That is, the CHARACTER is just another name for CHAR. You can use this subtype for the compatibility with ANSI/ISO and IBM types or when you want an identifier more expressive than CHAR.