Identifier 

Identifier A distinction is made between simple identifiers and special identifiers.

Syntax

<identifier> ::= <simple identifier> | <double quotes><special identifier><double quotes>

Simple identifier, double quotes, special identifier

Explanation

Identifiers can be entered in uppercase/lowercase characters.

Reserved keywords must not be used in simple identifiers. Reserved keywords, however, can be specified in the form of special identifiers.

Double quotes within a special identifier are represented by two consecutive quotes.

Simple identifier: reservation

Special identifier: "ADD"