AlterQuery  mv_target (children 2)
 ExpressionList (children 1)
  AlterCommand ADD_COLUMN (children 1)
   ColumnDeclaration b (children 2)
    DataType UInt8
    Function plus (children 1)
     ExpressionList (children 2)
      Identifier a
      Literal UInt64_1
 Identifier mv_target
