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????1?? ???????????????
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????v$session_longops???????????6???????SQL???
?????????о???????????????
????2?? ??乲???????
???????????OLTP??????app??к?????e??????????′???????????Parse??????????shared pool???CPU???????????
????3?? ?????????????
?????и???????????????
?????????multi-pass??????????????????????????????????й??
????4?? ???????SQL???
??????sys??У?????????????sql??????
??????????????????
???????DBA?????????????????????д洢???????
????5?? ?????????????
??????????????????????????????????????“?”??
???????????????????????м?????????????????Oracle???????????μ???????????????????????????????????·??
??????????????輰???????????????????CBO????????????????
????6?? ??????????????
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?????????Щ?????????????????
????7?? ?洢????????
????????洢???????????I/OЧ?????
?????????????ASM??RAID10??
????8?? ?????????????????
?????????C/S????????????????????B/S??
????9?? Redo Log ????????
????Redo log???????С?????????checkpoint????????????????I/O???
????Redo log???????????????????鵵???????redo entries?????????