通过案例学调优之--动态视图（v$bh和x$bh)

通过案例学调优之--动态视图（v$bh和x$bh)v$bh与x$bhv$bh:非常详细地记录了数据块在数据缓冲区内的使用情况，一条记录对应一个block的详细记录。v$bh来自于基表x

13:07:20 SYS@ test1 >desc v$bh  Name                                                              Null?    Type  ----------------------------------------------------------------- -------- --------------------------------------------  FILE#                                                                      NUMBER  BLOCK#                                                                     NUMBER  CLASS#                                                                     NUMBER  STATUS                                                                     VARCHAR2(10)  XNC                                                                        NUMBER  FORCED_READS                                                               NUMBER  FORCED_WRITES                                                              NUMBER  LOCK_ELEMENT_ADDR                                                          RAW(4)  LOCK_ELEMENT_NAME                                                          NUMBER  LOCK_ELEMENT_CLASS                                                         NUMBER  DIRTY                                                                      VARCHAR2(1)  TEMP                                                                       VARCHAR2(1)  PING                                                                       VARCHAR2(1)  STALE                                                                      VARCHAR2(1)  DIRECT                                                                     VARCHAR2(1)  NEW                                                                        CHAR(1)  OBJD                                                                       NUMBER  TS#                                                                        NUMBER  LOBID                                                                      NUMBER  CACHEHINT                                                                  NUMBER