NAME
CHECKPOINT - 强制一个事务日志检查点
SYNOPSIS
CHECKPOINT
DESCRIPTION 描述
预写式日志（Write-Ahead Logging (WAL)）缺省时在事务日志中每隔一段时间放一个检查点。 （要调整这个原子化的检查点间隔，你可以参考运行时选项 checkpoint_segments 和 checkpoint_segments 。） CHECKPOINT 强迫在命令声明时立即进行检查， 而不是等到下一次调度时的检查点。
检查点是一个事务日志训练中的点，在该点，所有数据文件都被更新以反映日志中的信息。 所有数据文件都将被冲刷到磁盘。请参考 Chapter 25 ``Write-Ahead Logging'' 获取更多有关 WAL 系统的信息。
只有超级用户可以调用 CHECKPOINT。 该命令不是设计用于正常操作过程中的。
COMPATIBILITY 兼容性
CHECKPOINT 命令是 PostgreSQL 语言的扩展。
#p#
NAME
CHECKPOINT - force a transaction log checkpoint
SYNOPSIS
CHECKPOINT
DESCRIPTION
Write-Ahead Logging (WAL) puts a checkpoint in the transaction log every so often. (To adjust the automatic checkpoint interval, see the run-time configuration options checkpoint_segments and checkpoint_timeout.) The CHECKPOINT command forces an immediate checkpoint when the command is issued, without waiting for a scheduled checkpoint.
A checkpoint is a point in the transaction log sequence at which all data files have been updated to reflect the information in the log. All data files will be flushed to disk. Refer to the the chapter called ``Write-Ahead Logging'' in the documentation for more information about the WAL system.
Only superusers may call CHECKPOINT. The command is not intended for use during normal operation.
COMPATIBILITY
The CHECKPOINT command is a PostgreSQL language extension.
