SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Function equals (children 1)
     ExpressionList (children 2)
      Function format (children 1)
       ExpressionList (children 3)
        Literal \'{}{}\'
        Function materialize (children 1)
         ExpressionList (children 1)
          Function toFixedString (children 1)
           ExpressionList (children 2)
            Literal \'a\'
            Literal UInt64_1
        Function materialize (children 1)
         ExpressionList (children 1)
          Literal \'b\'
      Literal \'ab\'
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.numbers
   Literal UInt64_5
