anchor.diff:      ;
   
   update: 
  -    updateClause 
  -    setClause 
  -    whereClause? 
  -    orderByClause? 
  -    limitClause?
  +    updateClause setClause whereClause? orderByClause? limitClause?
       ;
   
   setClause 
  
positive.code:     ;
  
  delete: 
      deleteClause 
      whereClause? 
      orderByClause? 
      limitClause?
      ;
  
  partitionClause 
  
negative.code:     ;
  
  groupByClause
      : GROUP BY groupByItem (COMMA groupByItem)* (WITH ROLLUP)? havingClause?
      ;
  
  havingClause
  