port "Print binary data as hex in the mysql client" by @dveeden

original code: mysql/mysql-server#118

MariaDB [test]> create table t1(id binary(16) primary key, name varchar(100));

Query OK, 0 rows affected (0.03 sec)

MariaDB [test]> insert into t1 values(unhex(replace(uuid(),'-','')), 'test 1');

Query OK, 1 row affected (0.00 sec)

MariaDB [test]> insert into t1 values(unhex(replace(uuid(),'-','')), 'test 2');

Query OK, 1 row affected (0.00 sec)

MariaDB [test]> insert into t1 values(unhex(replace(uuid(),'-','')), 'test 3');

Query OK, 1 row affected (0.00 sec)

MariaDB [test]> select * from t1;

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

| id | name |

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

| ^_?m?T?dl?^T?|H | test 1 |

| !?T?dl?^T?|H | test 2 |

| #t1?T??dl?^T??|H | test 3 |

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

3 rows in set (0.00 sec)

With the addition of this patch, the following is possible:

MariaDB [test]> select * from t1;

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

| id | name |

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

| 0x1FE6166DFF5411E6AB646C8814987C48 | test 1 |

| 0x21EFDCB2FF5411E6AB646C8814987C48 | test 2 |

| 0x237431D4FF5411E6AB646C8814987C48 | test 3 |

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

3 rows in set (0.00 sec)

MariaDB [test]> select * from t1 where id = 0x21EFDCB2FF5411E6AB646C8814987C48;

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

| id | name |

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

| 0x21EFDCB2FF5411E6AB646C8814987C48 | test 2 |

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

1 row in set (0.00 sec)

MariaDB [test]> select * from t1\G

*************************** 1. row ***************************

id: 0x1FE6166DFF5411E6AB646C8814987C48

name: test 1

*************************** 2. row ***************************

id: 0x21EFDCB2FF5411E6AB646C8814987C48

name: test 2

*************************** 3. row ***************************

id: 0x237431D4FF5411E6AB646C8814987C48

name: test 3

3 rows in set (0.01 sec)

This patch also introduces the new option --binary-as-hex=0 in

order to disable this new behavior.