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分享有关DBWN的锁的问题。
以下是俺看的一个QUEST的ORACLE XPERT的文章
As of Oracle 7.3, if blocks have their lock bit set (that is, they were modified by a transaction) then as they are written out of the cache, DBWn resets their lock bits back to unlocked status. In versions prior to 7.3 the blocks were written as-is and the next process to read them reset the lock bits. A dirty buffer is any buffer that has had any of its bits twiddled. Even if only the lock bit is turned on and no other changes are performed the block must be re-written to disk. Writes are always deferred if needed to optimize system I/O.
请问，如何去理解对于7。3以后ORACL在处理
DBWN时数据块被某一事物修改前后锁的变化？
As of Oracle 7.3, if blocks have their lock bit set (that is, they were modified by a transaction) then as they are written out of the cache, DBWn resets their lock bits back to unlocked status. In versions prior to 7.3 the blocks were written as-is and the next process to read them reset the lock bits. A dirty buffer is any buffer that has had any of its bits twiddled. Even if only the lock bit is turned on and no other changes are performed the block must be re-written to disk. Writes are always deferred if needed to optimize system I/O.
请问，如何去理解对于7。3以后ORACL在处理
DBWN时数据块被某一事物修改前后锁的变化？
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