摘要： This practice will demonstrate the concept of extent, wrap and shrink in rollback segment utilization. You will: Use the create rollback segment and alter rollback segment syntax. Examine the V$ROLLS... 阅读全文

摘要： Event:10210 See for similar events / parameters~~~~~~~~~~~Version/Use: 7.0 - 8.1.7 Check data block integrity after each modification 9.0+ This event is no longer valid. U... 阅读全文

摘要： Event:10060Text: dump predicates in optimizer (kko)-------------------------------------------------------------------------------Explanation: This is a special EVENT code. It should *... 阅读全文

摘要： Event:10211 See for similar events / parameters~~~~~~~~~~~ Version/Use: 7.0 - 8.1.7 Check data block integrity after each modification 9.0+ This event i... 阅读全文

摘要： The change vectors as constructed by the transaction layer are used by the cache layer to apply the physical block changes.Redo log ordering and recovery as well as read consistency are the fundamenta... 阅读全文

摘要： Stored objects And Transient objects are stored in the library cache, neither Temporary objects nor Permanent objects.The library cache is structured as a Hash table .But Library cache objects are c... 阅读全文

摘要： 4031_diag_script.zip1. SGA中的内存池包含不同大小的内存块。当数据库启动时，就有一个大的内存块分配并被hush buckets 里的空闲列表追踪。随着时间推移，随着内存的分配和释放，内存块被按照大小在不同的hush buckets间移动。当SGA里任何一个内存池里出现不能满足内部分配请求的情况时，ORA-04031就出现了。shared pool共享池的管理方式不同于其它的... 阅读全文

摘要： Reports index fragmentation statistics:==========Script #1:==========SET ECHO offREM NAME: TFSIFRAG.SQLREM USAGE:"@path/tfsifrag schema_name index_name"REM ------------------------------------------... 阅读全文

摘要： We can examine X$BH table to obtain buffer header information,The BH stands for buffer header.Structures that maintain a list of data buffer headers are called:Hash buckets.Hash buckets are grouped by... 阅读全文

摘要： Two purposes of latches were:Serialize Execution,Serialize AccessMatch the characteristics with latches and enqueues.Several modes of access EnqueueFIFO queue acquisition... 阅读全文