Oracle的X$表系列介绍之-X$KCCCP

X$KCCCP--[K]ernel [C]ache [C]ontrolfile management [c]heckpoint [p]rogress

其命名规则可以参考:X$ Tables and how the names are derived .

SQL> desc X$KCCCP
 Name              Null?    Type
 ----------------  -------- ------------------------
 ADDR                       RAW(4)
 INDX                       NUMBER
 INST_ID                    NUMBER
 CPTNO                      NUMBER
 CPSTA                      NUMBER
 CPFLG                      NUMBER
 CPDRT                      NUMBER
 CPRDB                      NUMBER
 CPLRBA_SEQ                 NUMBER
 CPLRBA_BNO                 NUMBER
 CPLRBA_BOF                 NUMBER
 CPODR_SEQ                  NUMBER
 CPODR_BNO                  NUMBER
 CPODR_BOF                  NUMBER
 CPODS                      VARCHAR2(16)
 CPODT                      VARCHAR2(20)
 CPODT_I                    NUMBER
 CPHBT                      NUMBER
 CPRLS                      VARCHAR2(16)
 CPRLC                      NUMBER
 CPMID                      NUMBER
 CPSDR_SEQ                  NUMBER
 CPSDR_BNO                  NUMBER
 CPSDR_ADB                  NUMBER

在此视图中,CPHBT字段代表checkpoint heartbeat,每三秒更新一次,并写入控制文件的heartbeat部分.

我们可以简单的通过如下方式查看CPHBT:

SQL> select cphbt from X$KCCCP;

     CPHBT
----------
 580567934