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Identifier (identifier). A distinction is made between simple identifiers (simple_identifier) and special identifiers (special_identifier).

Structure

Syntax Syntax

  1. <identifier> ::=
      <simple_identifier>
    | <double_quotes><special_identifier><double_quotes>
    
    <simple_identifier> ::=
      <first_character>[<identifier_tail_character>...]
    
    <special_identifier> ::=
      <special_identifier_character>...
    
    <double_quotes> ::=
      "
    
End of the code.

Example Example

Simple identifier: reservation

Special identifier: "ADD", "Example_1"

End of the example.
Simple Identifier

Syntax Syntax

  1. <simple_identifier> ::=
      <first_character>[<identifier_tail_character>...]
    
    <first_character> ::=
      <letter>
    | <extended_letter>
    | <language_specific_character>
    
    <identifier_tail_character> ::=
    | <digit>
    | <letter>
    | <extended_letter>
    | <language_specific_character>
    | <underscore>
    
End of the code.

Identifiers can be entered in uppercase/lowercase characters. When you specify simple identifiers (simple_identifier), upper and lower case are ignored, as the system always converts the identifier to upper case letters.

The first character in a simple identifier may not be a digit or underscore (underscore). Reserved keywords must not be used in simple identifiers.

Special Identifier

Syntax Syntax

  1. <special_identifier> ::=
      <special_identifier_character>...
    
    <special_identifier_character> ::=
    <!  any characters <character>, that can be linked in any sequence  !>
    
End of the code.

Identifiers can be entered in uppercase/lowercase characters. Special identifiers (special_identifier) are always used as specified in the database; that is upper and lower case characters are taken into account. Special identifiers are case sensitive.

If the name of a database object is to contain lowercase letters, special characters, reserved keywords, or blanks, the identifier must be specified as a special identifier that is enclosed in double quotation marks (double_quotes).

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

Explanations

Syntax Syntax

  1. <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
    
    <extended_letter> ::=
      # | @ | $
    
    <language_specific_character> ::=
    <!  <any letter that occurs in a northern, southern,
        or central European language and is not contained in the list of <letter>>
      | <for a UNICODE-enabled database: any character that is
        not included in the ASCII code list from 0 to 127>
    !>
    
    <digit> ::=
      0 | 1 | 2 | | 3 | 4 | 5 | 6 | 7 | 8 | 9
    
    <underscore> ::=
      _
    
End of the code.

Example Example

Language-specific characters

German umlauts: ä, ö, ü

French letters with a grave accent: à

End of the example.