create or replace table t (a varchar(32)) DEFAULT CHARSET=cp1257;

set histogram_type= JSON_HB, histogram_size= 1;

insert into t values ('foo'),(unhex('9C'));

analyze table t persistent for all;

select * from mysql.column_stats where table_name = 't';

select * from t;

# Cleanup

drop table t;

MariaDB [test]> select * from mysql.column_stats where table_name = 't';

+---------+------------+-------------+-----------+-----------+-------------+------------+---------------+-----------+-----------+---------------------------------------------------------------+

| db_name | table_name | column_name | min_value | max_value | nulls_ratio | avg_length | avg_frequency | hist_size | hist_type | histogram                                                     |

+---------+------------+-------------+-----------+-----------+-------------+------------+---------------+-----------+-----------+---------------------------------------------------------------+

| test    | t          | a           | foo       | �          |      0.0000 |     2.0000 |        1.0000 |         0 | JSON_HB   | {

  "histogram_hb_v2": [

    {

      "start": "foo"

    ]

  } |

+---------+------------+-------------+-----------+-----------+-------------+------------+---------------+-----------+-----------+---------------------------------------------------------------+

1 row in set (0.000 sec)

MariaDB [test]> 

MariaDB [test]> select * from t;

ERROR 4183 (HY000): Failed to parse histogram: Root JSON element must be a JSON object at offset 0.