SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Function sum (children 1)
     ExpressionList (children 1)
      Function CAST (children 1)
       ExpressionList (children 2)
        Identifier value
        Literal \'UInt64\'
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier test_alter_on_mutation
