我觉得我的商店有一个漏洞,因为我们没有一个可靠的过程来控制数据库模式更改的版本。我们做了很多备份,所以我们或多或少地得到了保护,但以这种方式依赖于最后一道防线是一种糟糕的做法。

令人惊讶的是,这似乎是一个共同的主线。与我交谈过的许多商店都忽略了这个问题,因为他们的数据库不会经常更改,他们基本上只是尽量做到一丝不苟。

不过,我知道这个故事是怎么发展的。这只是时间问题,迟早会出问题,会有东西丢失。

在这方面有什么最佳实践吗?你有哪些行之有效的策略?


当前回答

The most successful scheme I've ever used on a project has combined backups and differential SQL files. Basically we would take a backup of our db after every release and do an SQL dump so that we could create a blank schema from scratch if we needed to as well. Then anytime you needed to make a change to the DB you would add an alter scrip to the sql directory under version control. We would always prefix a sequence number or date to the file name so the first change would be something like 01_add_created_on_column.sql, and the next script would be 02_added_customers_index. Our CI machine would check for these and run them sequentially on a fresh copy of the db that had been restored from the backup.

我们还准备了一些脚本,开发人员可以用一个命令将本地db重新初始化到当前版本。

其他回答

我已经开始研究sqlHawk,它的目标是围绕这个问题提供(开源)工具。

它目前处于相当早期的阶段,但已经支持存储和执行存储过程以及运行脚本更新。

如果有任何人有时间看这个工具,我将非常感激。

为公然的自我推销道歉,但我希望这对某人有用!

You should never just log in and start entering "ALTER TABLE" commands to change a production database. The project I'm on has database on every customer site, and so every change to the database is made in two places, a dump file that is used to create a new database on a new customer site, and an update file that is run on every update which checks your current database version number against the highest number in the file, and updates your database in place. So for instance, the last couple of updates:

if [ $VERSION \< '8.0.108' ] ; then
  psql -U cosuser $dbName << EOF8.0.108
    BEGIN TRANSACTION;
    --
    -- Remove foreign key that shouldn't have been there.
    -- PCR:35665
    --
    ALTER TABLE     migratorjobitems
    DROP CONSTRAINT migratorjobitems_destcmaid_fkey;
    -- 
    -- Increment the version
    UPDATE          sys_info
    SET             value = '8.0.108'
    WHERE           key = 'DB VERSION';
    END TRANSACTION;
EOF8.0.108
fi

if [ $VERSION \< '8.0.109' ] ; then
  psql -U cosuser $dbName << EOF8.0.109
    BEGIN TRANSACTION;
    --
    -- I missed a couple of cases when I changed the legacy playlist
    -- from reporting showplaylistidnum to playlistidnum
    --
    ALTER TABLE     featureidrequestkdcs
    DROP CONSTRAINT featureidrequestkdcs_cosfeatureid_fkey;
    ALTER TABLE     featureidrequestkdcs
    ADD CONSTRAINT  featureidrequestkdcs_cosfeatureid_fkey
    FOREIGN KEY     (cosfeatureid)
    REFERENCES      playlist(playlistidnum)
    ON DELETE       CASCADE;
    --
    ALTER TABLE     ticket_system_ids
    DROP CONSTRAINT ticket_system_ids_showplaylistidnum_fkey;
    ALTER TABLE     ticket_system_ids
    RENAME          showplaylistidnum
    TO              playlistidnum;
    ALTER TABLE     ticket_system_ids
    ADD CONSTRAINT  ticket_system_ids_playlistidnum_fkey
    FOREIGN KEY     (playlistidnum)
    REFERENCES      playlist(playlistidnum)
    ON DELETE       CASCADE;
    -- 
    -- Increment the version
    UPDATE          sys_info
    SET             value = '8.0.109'
    WHERE           key = 'DB VERSION';
    END TRANSACTION;
EOF8.0.109
fi

我相信有更好的方法来做到这一点,但到目前为止,它对我来说是有效的。

“简短版本:将您的生产数据库转储到git存储库中,以实现即时备份解决方案。”

是的,我们的源代码控制我们的sql脚本也与subversion。这是一个很好的实践,您可以在需要时使用默认数据重新创建模式。

我使用ActiveRecord Migrations。这个Ruby gem可以在Rails项目之外使用,并且有适配器可以处理您遇到的大多数数据库。我的建议:如果你能够在Postgres上运行你的项目,你就会得到事务性的模式迁移。这意味着如果迁移只应用了一半,您不会最终得到一个损坏的数据库。