anchor.diff:      : C O N S T R A I N T S
       ;
   
  -CURRENT
  -    : C U R R E N T
  -    ;
  -
   CURRENT_TIMESTAMP
       : C U R R E N T UL_ T I M E S T A M P
       ;
  
positive.code: lexer grammar PostgreSQLKeyword;
  
  import Symbol;
     
  ACTION
      : A C T I O N
      ;
  
negative.code: ZONE
      : Z O N E
      ;
  
  
  