SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Asterisk
   TablesInSelectQuery (children 3)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 1)
          ExpressionList (children 1)
           Literal UInt64_2
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      Subquery (alias a) (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 1)
          ExpressionList (children 1)
           Literal UInt64_1
     TableJoin
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      Subquery (alias b) (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 1)
          ExpressionList (children 1)
           Literal UInt64_1
     TableJoin
