## Character

A character is an element of a character string or keyword.

### Syntax

<character> ::= <digit>
| <letter>
| <extended_letter>
| <hex_digit>
| <language_specific_character>
| <special_character>

#### Digits

<digit> ::= 0 | 1 | 2 | | 3 | 4 | 5 | 6 | 7 | 8 | 9

#### Letters

<letter> ::= A | B | C | D | E | F | G | H | I | J | K | L | M
| N | O | P | Q | R | S | T | U | V | W | X | Y | Z
| a | b | c | d | e | f | g | h | i | j | k | l | m
| n | o | p | q | r | s | t | u | v | w | x | y | z

#### Further Letters

<extended_letter> ::= # | @ | $

#### Hexadecimal Characters

<hex_digit> ::= 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9
| A | B | C | D | E | F
| a | b | c | d | e | f

#### Language-Specific Characters

A language-specific character language_specific_character is any letter that occurs in a northern, southern, or central European language and is not contained in the list of letters.

German umlauts: ä, ö, ü

French letters with a “grave” accent: à

If you have installed a UNICODE-enabled database instance, a language-specific character is a character that is not included in the ASCII code list from 0 to 127.

#### Special Characters

A special character is any character that is not contained in the following list:

● Digits

● Letters

● Further letters

● Hexadecimal characters

● Language-specific characters

● Characters that indicate the end of a line in a file

See also:

Character Set (token)

Literal (literal)