AlterQuery  test_new_col (children 2)
 ExpressionList (children 1)
  AlterCommand ADD_COLUMN (children 1)
   ColumnDeclaration csv_col3 (children 2)
    DataType String
    Function arrayElement (children 1)
     ExpressionList (children 2)
      Identifier csv_as_array
      Literal UInt64_3
 Identifier test_new_col
