alter table mysql.user add system versioning;

# Query OK, 2 rows affected (0.04 sec)

select user, host, sys_trx_start, sys_trx_end from mysql.user for system_time all;

# +------+-----------+----------------------------+----------------------------+

# | user | host      | sys_trx_start              | sys_trx_end                |

# +------+-----------+----------------------------+----------------------------+

# | root | localhost | 2017-12-28 19:40:13.453770 | 2038-01-19 05:14:07.999999 |

# | root | 127.0.0.1 | 2017-12-28 19:40:13.453770 | 2038-01-19 05:14:07.999999 |

# +------+-----------+----------------------------+----------------------------+

create user foo@localhost;

# Query OK, 0 rows affected (0.00 sec)

select user, host, sys_trx_start, sys_trx_end from mysql.user for system_time as of current_timestamp;

# +------+-----------+----------------------------+----------------------------+

# | user | host      | sys_trx_start              | sys_trx_end                |

# +------+-----------+----------------------------+----------------------------+

# | root | localhost | 2017-12-28 19:40:13.453770 | 2038-01-19 05:14:07.999999 |

# | root | 127.0.0.1 | 2017-12-28 19:40:13.453770 | 2038-01-19 05:14:07.999999 |

# +------+-----------+----------------------------+----------------------------+

select user, host, sys_trx_start, sys_trx_end from mysql.user for system_time all;

# +------+-----------+----------------------------+----------------------------+

# | user | host      | sys_trx_start              | sys_trx_end                |

# +------+-----------+----------------------------+----------------------------+

# | root | localhost | 2017-12-28 19:40:13.453770 | 2038-01-19 05:14:07.999999 |

# | root | 127.0.0.1 | 2017-12-28 19:40:13.453770 | 2038-01-19 05:14:07.999999 |

# | foo  | localhost | NULL                       | 0000-00-00 00:00:00.000000 |

# +------+-----------+----------------------------+----------------------------+

alter table mysql.proc add system versioning;

# Query OK, 2 rows affected (0.04 sec)

create procedure pr() begin end;

# ERROR 1805 (HY000): Column count of mysql.proc is wrong. Expected 21, found 23. The table is probably corrupted