A log chain begins with the first log backup taken after the database is created or when it is switched from the simple to the full or bulk-logged recovery model.

• 日志链的开始处是创建数据库后所做的第一个日志备份,或者是数据库从简单模式切换到完整模式或大容量日志恢复模式时所做的第一个日志备份。