Category: Oracle

/********* Wait.sql ************/ set pages 2000 set lines 132 column p1text format a18 column event format a35 column WT format 9999 column SW format 9999 select sid, event,p1text,p1raw,p1,p2,p3,seconds_in_Wait “SW”,Wait_time “WT” from v$session_wait where event not in( ‘KXFQ: Dequeue Range Keys – Slave’, ‘KXFQ: Dequeuing samples’, ‘KXFQ: kxfqcls – consumer closing TQ’, ‘KXFQ: kxfqdeq – dequeue…

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Renaming oracle instance (from UOCTEST to UAS) Note : Remember to rename datafile, logfile, controlfile, parameterfile and passwordfile. Aslo need to change listener. ******** Parameter File *************************** (1) check whether instance is using SPFIlE. using “show parameter spfile” (2) SQL> connect / as sysdba SQL> “create pfile from spfile” in 10g by default it will…

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Make sure the entry for your database SID in the ORATAB file ends in a capital “Y”. Eg: # $ORACLE_SID:$ORACLE_HOME:[N|Y] # ORCL:/u01/app/oracle/product/8.0.5:Y # The scripts for starting and stopping databases are: $ORACLE_HOME/bin/dbstart and dbshut. SQL*Net (or Net8) is started with the lsnrctl command. Add the following entries to your /etc/rc2.d/S99dbstart (or equivalent) file: su –…

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How does one list all installed Oracle products? One can display all installed products with version information by executing one of the following commands. For Oracle7 up to 8.0: cd $ORACLE_HOME/orainst ./inspdver For Oracle 8i and above: cd $ORACLE_HOME/install cat unix.rgs

Can one export directly to a tape drive? —————————————– One can use a tape device name instead of a normal file name. When using a device, one also needs to specify the VOLSIZE= parameter. Look at this example: exp userid/password file=/dev/rmt0 table=emp volsize=1.2G Note: The volume size is a number ending with a “m”, “k”,…

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If one cannot afford to buy extra disk space one can run the export and compress utilities simultaneously. This will prevent the need to get enough space for both the export file AND the compressed export file. Eg: # Make a pipe mknod expdat.dmp p # or mkfifo pipe # Start compress sucking on the…

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Metalink Performance Library Index

BENEFITS of Locally Managed Tablespaces ————————————— Locally managed tablespaces track all extent information in the tablespace itself, using bitmaps, resulting in the following benefits: * Improved concurrency and speed of space operations, because space allocations and deallocations predominantly modify locally managed resources (bitmaps stored in header files) rather than requiring centrally managed resources such as…

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True Session Wait Activity in Oracle 10g ======================================== Catching a session waiting on a resource used to be hit or miss. Let’s take a look at how Oracle has helped give us a better mousetrap for seeing the waits experienced by sessions. It used to be that a DBA would sit in front of the…

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Interpreting Wait Event “file#” and “block#” parameters ======================================================= This reference note describes how to interpret file# and block# parameters from wait events (eg: obtained from or from the WAIT trace lines in trace files). The text uses: &AFN to represent the absolute file number (file#) &BLOCKNO to represent the block number (block#) IMPORTANT: The details…

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