Oracle Dba Discussion Board

[KOTC]

[quote name='TheMonk' timestamp='1369268708' post='1303785913']
Guys ...

Oracle re-org ki and Shrink ki difference enti .. Botth do the same thing kada
[/quote]


HTH

[color=#282828][font=helvetica, arial, sans-serif][font=Tahoma, sans-serif]If a table with reclaimable space is not eligible for online segment shrink, or if you want to make changes to logical or physical attributes of the table while reclaiming space, you can use [/font][font=Tahoma, sans-serif][b]online table redefinition[/b][/font][font=Tahoma, sans-serif] as an alternative to segment shrink. Online redefinition is also referred to as [/font][font=Tahoma, sans-serif][b]reorganization[/b][/font][font=Tahoma, sans-serif]. Unlike online segment shrink, it requires extra disk space to be allocated. See [/font][url="http://docs.oracle.com/cd/B28359_01/server.111/b28310/tables007.htm#i1006754"]"Redefining Tables Online"[/url][font=Tahoma, sans-serif] for more information.[/font][/font][/color]


http://docs.oracle.com/cd/B28359_01/server.111/b28310/schema003.htm

[Gachibowli_Diwakar]

[quote name='IWillWin' timestamp='1369871675' post='1303804005']
Bhayyas Golden Gate loo sahayam kaavali .. Below is the scenario

A -- Production Server
B -- Some other Server
C -- ITL Server( I don't know what ITL is, but it is not Production server)

Last two years nunchi A loo Source database and B loo Target database vunaayi .... Golden Gate software A server loo vundi ..... Ippudu C source database kaavali and A Target database kaavali ... Is it possible to use the software in A or do we need to install new Golden gate software again???

Telisthey help cheyandi .. Thanks
[/quote] A machine lo unna software tar ball unte .. use that software and untar on machine C .. ledu ante take a tar of software from machine A ..

[accuman]

[font=arial, sans-serif][size=3]Database IT Team leader evvarikanna kavala try chettara?[/size][/font]

[accuman]

[b] Database Administrator & Senior Oracle DB[/b]


evvaru anna vunnara?

[KOTC]

[quote name='accuman' timestamp='1369971780' post='1303808293']
[b] Database Administrator & Senior Oracle DB[/b]


evvaru anna vunnara?
[/quote]

LTT

[KOTC]

If anybody knows about "Oracle Lock Escalation ".Please,explain

[nexus]

[size=4][font=Tahoma, sans-serif]A transaction holds exclusive row locks for all rows inserted, updated, or deleted within the transaction. Because row locks are acquired at the highest degree of restrictiveness, no lock conversion is required or performed.[/font]

[font=Tahoma, sans-serif]Oracle Database automatically converts a table lock of lower restrictiveness to one of higher restrictiveness as appropriate. For example, assume that a transaction uses a SELECT statement with the FOR UPDATE clause to lock rows of a table. As a result, it acquires the exclusive row locks and a row share table lock for the table. If the transaction later updates one or more of the locked rows, the row share table lock is automatically converted to a row exclusive table lock.[/font]
[font=Tahoma, sans-serif][b]Lock escalation[/b] occurs when numerous locks are held at one level of granularity (for example, rows) and a database raises the locks to a higher level of granularity (for example, table). For example, if a single user locks many rows in a table, some databases automatically escalate the user's row locks to a single table. The number of locks is reduced, but the restrictiveness of what is being locked is increased.[/font]

[font=Tahoma, sans-serif][i]Oracle Database never escalates locks.[/i] Lock escalation greatly increases the likelihood of deadlocks. Imagine the situation where the system is trying to escalate locks on behalf of transaction T1 but cannot because of the locks held by transaction T2. A deadlock is created if transaction T2 also requires lock escalation of the same data before it can proceed.[/font][/size]

[KOTC]

[quote name='nexus' timestamp='1370282479' post='1303818391']
[size=4][font=Tahoma, sans-serif]A transaction holds exclusive row locks for all rows inserted, updated, or deleted within the transaction. Because row locks are acquired at the highest degree of restrictiveness, no lock conversion is required or performed.[/font]

[font=Tahoma, sans-serif]Oracle Database automatically converts a table lock of lower restrictiveness to one of higher restrictiveness as appropriate. For example, assume that a transaction uses a SELECT statement with the FOR UPDATE clause to lock rows of a table. As a result, it acquires the exclusive row locks and a row share table lock for the table. If the transaction later updates one or more of the locked rows, the row share table lock is automatically converted to a row exclusive table lock.[/font]
[font=Tahoma, sans-serif][b]Lock escalation[/b] occurs when numerous locks are held at one level of granularity (for example, rows) and a database raises the locks to a higher level of granularity (for example, table). For example, if a single user locks many rows in a table, some databases automatically escalate the user's row locks to a single table. The number of locks is reduced, but the restrictiveness of what is being locked is increased.[/font]

[font=Tahoma, sans-serif][i]Oracle Database never escalates locks.[/i] Lock escalation greatly increases the likelihood of deadlocks. Imagine the situation where the system is trying to escalate locks on behalf of transaction T1 but cannot because of the locks held by transaction T2. A deadlock is created if transaction T2 also requires lock escalation of the same data before it can proceed.[/font][/size]
[/quote]

ardham ayi ardham avantantu undi vayya

[KOTC]

Oracle RAC meda interview questions evari dagara ayina dumps unte zara share cheyandi

[CheGuevara]

[quote name='accuman' timestamp='1369971738' post='1303808292']
[font=arial, sans-serif][size=3]Database IT Team leader evvarikanna kavala try chettara?[/size][/font]
[/quote]

Pm details plz..

[nexus]

[quote name='STFU' timestamp='1370283111' post='1303818432']

ardham ayi ardham avantantu undi vayya
[/quote]

General ga konni database systems lo finite(limited) number of locks matrame undachu.Lets assume it 500. Alanti vatilo, suppose EMP ane oka table undhi. Suppose adhi 4 blocks occupy cheskunindhi ankundhaam. Okko block lo 200 rows undhi ani ankundhaam. Ippudu suppose session S1, oka transaction T1 ni run chesthu EMP table ni update chesthondhi, adhi oka block B1 lo already 100 rows paina row exclusive lock acquire cheskondhi. Ante motham database system lo 100 locks ni S1 thiskundhi. migilindhi 400 locks. Apudu rdbms system ila ankuntundhi...dhiniki oka dhanike 20% of locks ichesaanu.. paiga adhi acquire cheskunna row level locks anni oka block lo ne undhi...dhini mokaniki oka entire block level lock ichesethe saripothundhi..migilina 99 locks naaku ichesthundhi..ani ankuntundhi. So apudu row lock escalation to block lock jarigi...oka block level lock isthundhi aat transaction T1 ki and migilina 99 locks thiseskuntundhi.

[KOTC]

[quote name='nexus' timestamp='1370284045' post='1303818512']

General ga konni database systems lo finite(limited) number of locks matrame undachu.Lets assume it 500. Alanti vatilo, suppose EMP ane oka table undhi. Suppose adhi 4 blocks occupy cheskunindhi ankundhaam. Okko block lo 200 rows undhi ani ankundhaam. Ippudu suppose session S1, oka transaction T1 ni run chesthu EMP table ni update chesthondhi, adhi oka block B1 lo already 100 rows paina row exclusive lock acquire cheskondhi. Ante motham database system lo 100 locks ni S1 thiskundhi. migilindhi 400 locks. Apudu rdbms system ila ankuntundhi...dhiniki oka dhanike 20% of locks ichesaanu.. paiga adhi acquire cheskunna row level locks anni oka block lo ne undhi...dhini mokaniki oka entire block level lock ichesethe saripothundhi..migilina 99 locks naaku ichesthundhi..ani ankuntundhi. So apudu row lock escalation to block lock jarigi...oka block level lock isthundhi aat transaction T1 ki and migilina 99 locks thiseskuntundhi.
[/quote]

http://arup.blogspot.com/2011/01/how-oracle-locking-works.html

idi edo dorikindi bhayya lock manager inka lock management in oracle by arup nanda idi chadivka baga ardham avutundi emo

[nexus]

evaikaina panikosthadhemo ani paste chesthunna...

Database lo alert log lo record aina errors/contents chudalante kindha sql st use avthundhi

break on timestamp skip 1
set lin 300 pages 300
col message_text format a100
select inst_id,to_char(ORIGINATING_TIMESTAMP,'DD-MON-YY HH24') timestamp, substr(MESSAGE_TEXT, 1, 300) message_text,count(*) cnt
from X$DBGALERTEXT
where (MESSAGE_TEXT like '%ORA-%')
and ORIGINATING_TIMESTAMP > to_timestamp_tz('04/05/2013:20:00:00','mm/dd/yyyy:hh24:mi:ss')
and ORIGINATING_TIMESTAMP < to_timestamp_tz('04/08/2013:12:00:00','mm/dd/yyyy:hh24:mi:ss')
group by inst_id,to_char(ORIGINATING_TIMESTAMP,'DD-MON-YY HH24'),substr(MESSAGE_TEXT, 1, 300)
order by inst_id,2,count(*);


Same stuff adrci dwara kuda thelsukovachu

[KOTC]

[quote name='nexus' timestamp='1370540361' post='1303829253']
evaikaina panikosthadhemo ani paste chesthunna...

Database lo alert log lo record aina errors/contents chudalante kindha sql st use avthundhi

break on timestamp skip 1
set lin 300 pages 300
col message_text format a100
select inst_id,to_char(ORIGINATING_TIMESTAMP,'DD-MON-YY HH24') timestamp, substr(MESSAGE_TEXT, 1, 300) message_text,count(*) cnt
from X$DBGALERTEXT
where (MESSAGE_TEXT like '%ORA-%')
and ORIGINATING_TIMESTAMP > to_timestamp_tz('04/05/2013:20:00:00','mm/dd/yyyy:hh24:mi:ss')
and ORIGINATING_TIMESTAMP < to_timestamp_tz('04/08/2013:12:00:00','mm/dd/yyyy:hh24:mi:ss')
group by inst_id,to_char(ORIGINATING_TIMESTAMP,'DD-MON-YY HH24'),substr(MESSAGE_TEXT, 1, 300)
order by inst_id,2,count(*);


Same stuff adrci dwara kuda thelsukovachu
[/quote]


GP

[KOTC]

em ayina telisina Oracle DBA requirments zara pm cheyandi vayyas