SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 2)
    Function sum (children 1)
     ExpressionList (children 1)
      Identifier val
    Function count (children 1)
     ExpressionList (children 1)
      Identifier val
   TablesInSelectQuery (children 2)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier tab1
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      TableIdentifier tab2
     TableJoin (children 1)
      Function or (children 1)
       ExpressionList (children 2)
        Function equals (children 1)
         ExpressionList (children 2)
          Function minus (children 1)
           ExpressionList (children 2)
            Identifier b1
            Literal UInt64_2
          Identifier a2
        Function equals (children 1)
         ExpressionList (children 2)
          Identifier a1
          Identifier b2
   Set