SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Asterisk
   TablesInSelectQuery (children 2)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Function cluster (alias A) (children 1)
       ExpressionList (children 2)
        Identifier test_cluster_two_shards
        Identifier system.one
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      Subquery (alias B) (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 2)
          ExpressionList (children 1)
           Asterisk
          TablesInSelectQuery (children 1)
           TablesInSelectQueryElement (children 1)
            TableExpression (children 1)
             Function cluster (children 1)
              ExpressionList (children 2)
               Identifier test_cluster_two_shards
               Identifier system.one
     TableJoin (children 1)
      Function equals (children 1)
       ExpressionList (children 2)
        Identifier A.dummy
        Identifier B.dummy
