When creating snapshot, Oracle collects data from operating system and the dynamic performance views, known as v$ (pronounced “v-dollar”) tables, which reside in memory. The collected data is then stored in the corresponding DBA_HIST_* tables within the SYSAUX tablespace.
The following table displays a list (incomplete) of the DBA_HIST_* views and their corresponding V$ performance views in Oracle:
DBA_HIST_* View | Corresponding V$ View(s) |
|---|---|
| DBA_HIST_ACTIVE_SESS_HISTORY | V$ACTIVE_SESSION_HISTORY |
| DBA_HIST_BASELINE | V$BASELINE |
| DBA_HIST_SNAPSHOT | V$SNAPSHOT |
| DBA_HIST_DATABASE_INSTANCE | V$DATABASE, V$INSTANCE |
| DBA_HIST_SYSSTAT | V$SYSSTAT |
| DBA_HIST_SYSTEM_EVENT | V$SYSTEM_EVENT |
| DBA_HIST_WAITSTAT | V$WAITSTAT |
| DBA_HIST_SEG_STAT | V$SEGSTAT |
| DBA_HIST_SEG_STAT_OBJ | V$SEGSTAT_OBJ |
| DBA_HIST_FILESTATXS | V$FILESTAT |
| DBA_HIST_LATCH | V$LATCH |
| DBA_HIST_LATCH_MISSES_SUMMARY | V$LATCH_MISSES |
| DBA_HIST_MEMORY_STAT | V$MEMORY_STAT |
| DBA_HIST_OSSTAT | V$OSSTAT |
| DBA_HIST_PGASTAT | V$PGASTAT |
| DBA_HIST_SGASTAT | V$SGASTAT |
| DBA_HIST_SYSMETRIC | V$SYSMETRIC |
| DBA_HIST_SYSMETRIC_SUMMARY | V$SYSMETRIC_SUMMARY |
| DBA_HIST_SYS_TIME_MODEL | V$SYS_TIME_MODEL |
| DBA_HIST_SQLSTAT | V$SQL |
| DBA_HIST_SQLTEXT | V$SQLTEXT |
| DBA_HIST_SQL_PLAN | V$SQL_PLAN |
| DBA_HIST_SQL_SUMMARY | V$SQL_SUMMARY |
| DBA_HIST_SQL_WORKAREA_HISTOGRAM | V$SQL_WORKAREA_HISTOGRAM |
| DBA_HIST_SQL_WORKAREA | V$SQL_WORKAREA |
| DBA_HIST_SQL_WORKAREA_ACTIVE | V$SQL_WORKAREA_ACTIVE |
| DBA_HIST_SYSSTAT | V$SYSSTAT |
| DBA_HIST_SYSTEM_EVENT | V$SYSTEM_EVENT |
| DBA_HIST_WAITCLASSMETRIC | V$WAITCLASSMETRIC |
| DBA_HIST_WAITCLASSMETRIC_HISTORY | V$WAITCLASSMETRIC_HISTORY |
| DBA_HIST_WAITCLASS_EVENT | V$WAITCLASS_EVENT |
| DBA_HIST_WAITCLASS_STAT | V$WAITCLASS_STAT |
| DBA_HIST_EVENT_HISTOGRAM | V$EVENT_HISTOGRAM |
| DBA_HIST_SERVICE_STAT | V$SERVICE_STAT |
| DBA_HIST_SERVICE_WAIT_CLASS | V$SERVICE_WAIT_CLASS |
| DBA_HIST_WR_CONTROL | V$WR_CONTROL |
Yuan Yao, An Oracle ACE's Blog 
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