I am going to talk about Some Oracle Statistics Table that will be useful for tuning your database , and gathering information about your database , these table are very useful
For example Dynamic Performance View :
**The below query will gives you the most sql statement taking more time in the CPU .
1-Select Sql_text , executions from v$sqlstats where cpu_time > 1000 ;
**Below Query Gives you some Details about Specific Machine
2-Select * from v$session where machine = ‘OSAMA_PC’ and where
logon_time > sysdate -1 ;
**finally , Lock in your database
3- select sid,ctime from v$lock where block > 0 ;
Statistics Tables are :
**Display System Wide Statistics :
**Display Session-Related Statistics
**Display Service-Related Statistics
V$Session_Event : Session Wait By event for each session had to wait .
V$Session_Wait : Session Wait By Event For current active session that are waiting .
V$System_Event : Total waits for an event (All Session Together).
Wait Event : Information About session that had to wait or must wait for Different Reasons (V$Event_name).
Some Other Useful Tables :