AlterQuery  default_table (children 2)
 ExpressionList (children 1)
  AlterCommand MODIFY_COLUMN (children 1)
   ColumnDeclaration enum_column (children 2)
    DataType Enum8 (children 1)
     ExpressionList (children 3)
      Function equals (children 1)
       ExpressionList (children 2)
        Literal \'undefined\'
        Literal UInt64_0
      Function equals (children 1)
       ExpressionList (children 2)
        Literal \'fox\'
        Literal UInt64_1
      Function equals (children 1)
       ExpressionList (children 2)
        Literal \'index\'
        Literal UInt64_2
    Literal \'undefined\'
 Identifier default_table
