PostgreSQL 10.0 preview 功能增强 - 支持EUI-64格式MAC地址类型
背景
PostgreSQL 是全球最先进的开源数据库，所谓先进，体现在很多方面：
支持扩展类型
支持扩展操作符
支持扩展函数
支持扩展窗口
支持扩展聚合
支持扩展采样
支持扩展扫描
支持扩展索引，内置8种索引
支持扩展访问方法
支持扩展插件
支持扩展。。。。。。
支持丰富的SQL标准
支持丰富的内置类型，比如很早以前就支持了MAC地址数据类型，随着时间点推移，以往48位的MAC地址库可能很快会耗尽，现在提出了64位MAC地址的标准，PostgreSQL 10.0很快就会支持它。
可能直接在原有MAC地址类型中扩展，也可能新增eui64类型.
There was bug that is raised in [1] related to storing EUI-64 mac address
in PostgreSQL MAC address datatype.
As the current macaddr datatype stores only 48 bit MAC address only, and
now a days
people are adopting to EUI-64 format of MAC address. So it better to add
the support
in PostgreSQL.
Here I attached a POC patch that adds the support for EUI-64 MAC address
storage with a
new datatype macaddr64. Currently this type takes only EUI-64 datatype, not
accepts 48
bit MAC address.
Before continuing and adding more details for macaddr64 datatype, it is not
possible to
add the support for current macaddr datatype as it is a fixed size datatype
that is stored
in the disk. So any enhancements to change it from 48 to 64 bit will give
problems to
pg_upgrade.
As we are moving to PostgreSQL 10, so are there any plans of backward
compatiblity
breakage, so the existing macaddr datatype itself can be changed to support
both
48 and 64 bit MAC addresses. If not, I will try update the POC patch with
more details
similar like macaddr datatype.
[1] -
https://www.postgresql.org/message-id/20161010162001.1413.12486%40wrigleys.postgresql.org
Regards,
Hari Babu
Fujitsu Australia
这个patch的讨论，详见邮件组，本文末尾URL。
PostgreSQL社区的作风非常严谨，一个patch可能在邮件组中讨论几个月甚至几年，根据大家的意见反复的修正，patch合并到master已经非常成熟，所以PostgreSQL的稳定性也是远近闻名的。
参考
https://commitfest.postgresql.org/13/837/
https://www.postgresql.org/message-id/flat/CAJrrPGcUi8ZH+KkK+=TctNQ+EfkeCEHtMU_yo1mvX8hsk_ghNQ@mail.gmail.com#CAJrrPGcUi8ZH+KkK+=TctNQ+EfkeCEHtMU_yo1mvX8hsk_ghNQ@mail.gmail.com