other_boolean_form ::= 
 {collection_name.EXISTS (index)
 | {
      cursor_name
    | cursor_variable_name
    | :host_cursor_variable_name
    | SQL
   }%{FOUND | ISOPEN | NOTFOUND} 
  | expression {
                   relational_operator expression
                  | IS [NOT] NULL
                  | {  [NOT] LIKE pattern
                      | [NOT] BETWEEN expression AND expression
                      | [NOT] IN (expression [, expression]...
                    ) 
                } 
 }