Последние новости
Москвичей призвали не ждать «дружную» весну14:57，详情可参考新收录的资料
Российский врач вернется к работе после истекшей кровью пациентки14:48。新收录的资料对此有专业解读
You might have noticed the row estimates (599 and 28,458) are lower than you'd expect for a 50-million-row table. The planner checks the actual physical file size. Our table is only 74 pages on disk, not the 123,513 we injected. Hence the planner scales reltuples down proportionally. The absolute numbers shrink, but the ratios between them stay correct, and it's the ratios that determine plan shape. When you use pg_dump --statistics-only in practice, you're typically restoring into a database with comparable data volume, so the estimates align naturally.，这一点在新收录的资料中也有详细论述
Thus a long-running read transaction can prevent a checkpointer from