If the roll forward set has not been rolled forward far enough to be consistent with the database, the undo phase cannot occur.

如果前滚集前滚得不够远，无法与数据库一致，则不会出现撤消阶段。

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If logretain is set to "recovery" or userexit is set to "Yes" (see below), the active log files will be retained and become online archive log files for use in roll-forward recovery.

如果logretain设置成“Recovery”或者userexit设置成“Yes”(请参阅下一节)，将保留活动日志文件，而且这些文件将变成联机归档日志文件，以便在前滚恢复中使用。

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If logretain is set to "recovery" or userexit is set to "Yes" (see below), the active log files will be retained and become online archive log files for use in roll-forward recovery.

如果logretain设置成“Recovery”或者userexit设置成“Yes”(请参阅下一节)，将保留活动日志文件，而且这些文件将变成联机归档日志文件，以便在前滚恢复中使用。

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