SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Function sum (children 1)
     ExpressionList (children 1)
      Function toUInt64OrZero (children 1)
       ExpressionList (children 1)
        Identifier str
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier lc_big_dict