Finding free/used temporary table space in Oracle
If you’re a freak who work around with Oracle as backend, you would face the sitution where the oracle temporary space would be exhausted. The usage temporary tablespace can’t be found out exactly using DBA_FREE_SPACE. To find out the true value of temporary table space we may need to use V$TEMP_SPACE_HEADER data dictonary. SELECT tablespace_name,
Finding locked objects in Oracle
If you’re wondering why particular query or procedure is talking a long such a long time to run; then make sure you check out whether the object you’re accessing is locked or not. There are quite a few dba views available to make our task less complicated. You can use the below query which will
Oracle server uptime
The following query works well with Oracle 9i. i’ve no clue whether this works with others too or not. SELECT TO_CHAR (startup_time, 'DD-MON-YYYY HH24:MI:SS') "DB Startup Time" FROM SYS.v_$instance; even there is possiblity to find the startup time by quering logon_time from sys.v_$session view.
Oracle Hidden Parameters
Oracle initialization or INIT.ORA parameters with an underscore in front are hidden or unsupported parameters. One can get a list of all hidden parameters by executing this query: SELECT * FROM SYS.x$ksppi WHERE SUBSTR (ksppinm, 1, 1) = '_'; The following query displays parameter names with their current value: SELECT a.ksppinm "Parameter", b.ksppstvl "Session Value",
Rename Oracle database username
No, this is not available till now in Oracle and has been noted down as a enhancement request. Still here is a workaround way of doing that: Do a user-level export of user A create new user B import system/manager from user=A to user=B drop user A