Character Set (token)

A character set (token) comprises a series of characters that are combined to form a lexical unit. A distinction is made between regular (regular_token) and delimiter (delimiter_token) tokens.

Structure

Syntax Syntax

<token> ::=
  <regular_token>
| <delimiter_token>

<regular_token> ::=
  <literal>
| <keyword>
| <identifier>
| <parameter_name>

<delimiter_token> ::=
  <vertical_slash>
| , | . | + | - | * | / | < | > | <> | != | = | <= | >=
| ~= <!  for computers with ASCII code  !>
| ~< <!  for computers with ASCII code  !>
| ~> <!  for computers with ASCII code  !>

<vertical_slash> ::=
  |

End of the code.

Example Example

SELECT * FROM reservation

ALTER TABLE reservation DROP FOREIGN KEY customer_reservation

'Reisen10'

End of the example.

Explanation

Each token can be followed by any number of blanks. Each regular token (regular_token) must be followed by a delimiter token (delimiter_token) or a blank.

Quotation marks within a special identifier are represented by two consecutive quotation marks.

More Information

Identifier (identifier)