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November | 2012 | musingdba
https://musingdba.wordpress.com/2012/11
8230; to an idle instance :). A Short Guide to Oracle SQL [I] – RDBMS Basic Concepts. Posted by madhurendra shrivastav. November 29, 2012. The following post(s) is just a review of RDBMS/SQL fundamentals what learned when I start using ORACLE and during SQL certification exam. I’ll try to put things in an ordered manner. The posts will have links to other blogs and oracle doc which helps me to understand SQL. Your comments and feedback are welcome. Database … Continue reading →. November 3, 2012.
hourim.wordpress.com
Mohamed Houri’s Oracle Notes | Qui se conçoit bien s’énonce clairement | Page 2
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Mohamed Houri’s Oracle Notes. September 5, 2015. Bind aware secret sauce (again). 8212; hourim @ 8:21 am. I am sure many of you have already become bored by my posts on adaptive cursor sharing. I hope this article will be the last one🙂. In part III. Of the installment I was unable to figure out the secret sauce Oracle is using to mark a cursor bind aware when count of the 3 buckets. Of a bind sensitive cursor are greater than 0. To make things simple I created the following function. Now change again th...
marogel.wordpress.com
2014 November « Sokrates on Oracle
https://marogel.wordpress.com/2014/11
An answer to everything. Annals of Oracle's Improbable Errors. Frank Zhou's collection. Inside the black magic. Sayan's sql observations. Select concepts from sql. Archive for November, 2014. Why is it not possible to raise an exception when handling no data needed? Posted by Matthias Rogel. On 8 November 2014. It seems impossible to raise an exception when handling no data needed. As expected, we handle exception raised by division by zero, there we dbms output some info and then raise program error.
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2015 March « Sokrates on Oracle
https://marogel.wordpress.com/2015/03
An answer to everything. Annals of Oracle's Improbable Errors. Frank Zhou's collection. Inside the black magic. Sayan's sql observations. Select concepts from sql. Archive for March, 2015. Overview of all time changes this year via SQL. Posted by Matthias Rogel. On 30 March 2015. Inspired by Laurent Schneider’s remark concerning special time changes in Lord Howe Island. Create a free website or blog at WordPress.com. Follow “Sokrates on Oracle”. Get every new post delivered to your Inbox.
hourim.wordpress.com
Degree of Parallelism is 16 because of table property | Mohamed Houri’s Oracle Notes
https://hourim.wordpress.com/2015/08/04/degree-of-parallelism-is-16-because-of-table-property
Mohamed Houri’s Oracle Notes. August 4, 2015. Degree of Parallelism is 16 because of table property. 8212; hourim @ 10:11 am. I have been pleasantly surprised by the following Note at the bottom of an execution plan coming from a 12.1.0.2.0 Oracle instance. As you can point it out, thanks to the above Note, we can immediately guess that the Optimizer decided to run the query in parallel because the T PAR table has been decorated with a DOP of 16. A nice 12c add. Unfortunately there is no Note indicating ...
hourim.wordpress.com
Resumable time out | Mohamed Houri’s Oracle Notes
https://hourim.wordpress.com/2015/02/14/resumable-time-out
Mohamed Houri’s Oracle Notes. February 14, 2015. 8212; hourim @ 9:47 am. I was trying to create a very big table through a. Create table as select. I launched the create table and started monitoring it with Tanel Poder snapper script, v$active session history and the Real Time SQL Monitoring feature ( RTSM. This is what the monitoring was showing. However few minutes later Tanel Poder. Snapper started showing the following dominant wait event. No available free space left in TEMP tablespace. Popping up i...
hourim.wordpress.com
Why Dynamic Sampling has not been used? | Mohamed Houri’s Oracle Notes
https://hourim.wordpress.com/2015/06/12/why-dynamic-sampling-has-not-been-used
Mohamed Houri’s Oracle Notes. June 12, 2015. Why Dynamic Sampling has not been used? 8212; hourim @ 10:15 am. Experienced tuning guys are known for their pronounced sense of looking at details others are very often ignoring. This is why I am always paying attention to their answers in otn and oracle-l list. Last week I have been asked to look at a query performing badly which has been monitored via the following execution plan:. As you can see apart from the optimizer index cost adj. About dynamic sampli...
hourim.wordpress.com
August | 2015 | Mohamed Houri’s Oracle Notes
https://hourim.wordpress.com/2015/08
Mohamed Houri’s Oracle Notes. August 21, 2015. Cardinality Feedback: a practical case. 8212; hourim @ 5:36 pm. Here it is an interesting case of cardinality feedback collected from an 11.2.0.3 running system. A simple query against a single table has a perfect first execution response time with, according to the human eyes, a quite acceptable difference between Oracle cardinality estimates and actual rows as shown below:. It might be “possible” that when Oracle rounds up its cardinality estim...SQL selec...
hourim.wordpress.com
Stressed ASH | Mohamed Houri’s Oracle Notes
https://hourim.wordpress.com/2015/07/09/stressed-ash
Mohamed Houri’s Oracle Notes. July 9, 2015. 8212; hourim @ 5:29 pm. It is well known that any record found in dba hist active session history has inevitably been routed there from v$active session history. If so, then how could we interpret the following cut and past from a running production system? 12,950 snapshots of SQL*Net break/reset to client. And 12,712 snapshots of an enq: TM – contention. Wait events in AWR not found in ASH. How can we interpret this situation? Typically the activity is mainly ...
hourim.wordpress.com
Real Time SQL Monitoring oddity | Mohamed Houri’s Oracle Notes
https://hourim.wordpress.com/2015/06/23/real-time-sql-monitoring-oddity
Mohamed Houri’s Oracle Notes. June 23, 2015. Real Time SQL Monitoring oddity. 8212; hourim @ 1:45 pm. This is a small note about a situation I have encountered and which I thought it is worth sharing with you. There was an insert/select executing in parallel DOP 16 on a 11.2.0.3 Oracle database for which the end user was complaining about the exceptional time it was taking without completing. Since the job was still running I tried getting its Real Time SQL monitoring report:. How could this be possible?
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