Identifier ( identifier). A distinction is made between simple identifiers and special identifiers.
<identifier> ::= <simple_identifier> | <double quotes><special_identifier><double_quotes>
simple_identifier, double_quotes, special_identifier
Identifiers can be entered in uppercase/lowercase characters. When you specify simple identifiers, upper and lower case are ignored, as the system always converts the identifier to upper case letters.
Reserved keywords must not be used in simple identifiers. Reserved keywords, however, can be specified in the form of special identifiers.
Double quotation marks within a special identifier are represented by two consecutive quotation marks.
Simple identifier: reservation
Special identifier: "ADD"