anchor.diff:  INNER: 'INNER';
   INPUT: 'INPUT';
   INSERT: 'INSERT';
  -INTEGER: 'INTEGER';
   INTERSECT: 'INTERSECT';
   INTERVAL: 'INTERVAL';
   INTO: 'INTO';
  
positive.code:     | FILTER | FIRST | FOLLOWING | FORMAT | FUNCTIONS
      | GRANT | GRANTS | GRAPHVIZ
      | HOUR
      | IF | INCLUDING | INPUT | INTEGER | INTERVAL | ISOLATION
      | LAST | LATERAL | LEVEL | LIMIT | LOGICAL
      | MAP | MINUTE | MONTH
      | NFC | NFD | NFKC | NFKD | NO | NULLIF | NULLS
  
negative.code: THEN: 'THEN';
  TIME: 'TIME';
  TIMESTAMP: 'TIMESTAMP';
  TO: 'TO';
  TRANSACTION: 'TRANSACTION';
  TRUE: 'TRUE';
  