For about fifteen years, the standard answer to “this table is bloated, what do I actually do about it” has been one of the out-of-tree options: pg_repack (the extension), pg_squeeze (Antonin...

PostgreSQL 19引入了REPACK的CONCURRENTLY选项，允许在不获取独占锁的情况下重组表。该功能通过共享更新锁创建初始副本，并利用并发后台工作者进行逻辑解码。尽管存在复制槽资源稀缺和死锁风险等问题，但设计和代码已基本完成，预计将在后续更新中解决。测试结果显示，重组后表大小显著减少，插入性能略有下降，但整体影响不大。

PostgreSQL 19引入了REPACK命令，整合了VACUUM FULL和CLUSTER的功能，简化了用户理解，同时保留了旧命令。REPACK支持重写表以回收磁盘空间，并提供新的进度视图pg_stat_progress_repack。尽管当前不支持并发模式，但未来可能会增加此功能。该命令使用简单，允许用户选择VERBOSE和ANALYZE等选项。

As the database size increases and the number of transactions per second rise, you'll inevitably face the challenge of the table bloat. Although PostgreSQL assists as much as possible with its...