SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Function equals (children 1)
     ExpressionList (children 2)
      Literal UInt64_8
      Function position (children 1)
       ExpressionList (children 2)
        Literal \'abcdefgh\'
        Function materialize (children 1)
         ExpressionList (children 1)
          Literal \'h\'
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.numbers
   Literal UInt64_10