I find that when people are designing Oracle RAC architecture, they often do not think of N+1 redundancy in their implementation plans. There are two reasons to implement Oracle RAC, availability and scalability. For the purposes of this discussion, I am focusing only on the availability side. If your RAC deployments are for scalability reasons …
Category: Oracle
Apr 05
V$SQL_SHARED_CURSOR TOP_LEVEL_RPI_CURSOR
I was working with an individual on a question in the MOSC forums recently where they asked about the TOP_LEVEL_RPI_CURSOR column of the V$SQL_SHARED_CURSOR view. There is little documentation on what this column is trying to tell the DBA. All the Oracle docs say is that this column contains “(Y|N) Is top level RPI cursor”. So …
Mar 08
SQL Server 2016 on Linux
Yesterday, Microsoft announced that it will be shipping a version of SQL Server 2016 (to be released later this year) that will run on Linux. It didn’t take long for the media to get the word out. I quickly found a story here and here. Right now, SQL Server 2016 is only available for early …
Feb 18
Oracle 12c IDENTIFIED BY VALUES
Since I can recall in my career working with Oracle, I’ve been able to modify a user’s password to the password hash. The trick I’ve sometimes employed was to store the userid/password hash, change the password to something I know, connect to the database as that user and then do my work. When done with …
Feb 17
A Tale Of Two Clustering Factors
I was looking at a post on the MOSC forums today about the Clustering Factor (CF) for an index. One thing that people tend to forget when talking about the CF is that while the DBA can do some reorg activity to improve the CF for an index, it will potentially come at the expense …
Jan 29
Complacency leads to: Risk Becomes Reality
I was participating in a recent thread on the OTN community where someone was asking questions about downgrading after a database upgrade. One of the responses asked how many people actually practice database downgrades. I created this poll to find out. I was surprised to find one contribution to that thread which said: I have …
Jan 26
Identifying ASH Sequence Contention in RAC
In Chapter 3 of Oracle RAC Performance Tuning, I showed how improper CACHE values for sequences can cause poor performance in Oracle RAC. I also showed how to spot sequence contention when looking at a session’s wait events. Today, I was working with a developer who was creating a new sequence. The developer had a …
Dec 28
SQL Developer 4.1.3 Released
The newest version of SQL Developer was released while I was out of the office last week. The download is in the usual place. http://www.oracle.com/technetwork/developer-tools/sql-developer/downloads/index.html According to viagra pills for women sexologists, there are multiple reasons for this secrecy. During that time, liver bile is redirected to generic cialis the gallbladder. buy bulk viagra …
Dec 22
A Trip Through the GIMR
Oracle Grid Infrastructure includes the Cluster Health Monitor (CHM) which regularly captures OS-related performance information. In early versions, CHM use a Berkeley DB for its data store. In Grid Infrastructure 12.1.0.2, it is now required to use an Oracle database for the data store. This Oracle database is called the Grid Infrastructure Management Repository (GIMR). …
Dec 11
LongOpsWatcher in SQL Dev
I saw a video of someone who used the new command line utility, sqlcl to create a bar graph showing the progress of long operations in Oracle, as seen from V$SESSION_LONGOPS. That video inspired me to do something similar in SQL Developer. Below is a video of LongOpsWatcher in action. You can see the time …
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@sacrophyte That was an old recommendation which is probably out of date now. When I look at the 19c doc for that p… https://t.co/h0VwGJECvH
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Also in that note is "We decided to not promote our Database 20c Preview version to General Availability. Instead,… https://t.co/bvUcRKQ9gt
