12cR2 real-time materialized view (on query computation)
Materialized views is a very old feature (you may remember that it was called snapshots a long time ago). It has all advantages of a view, as you can define any select statement that joins, filters,...
View Article12cR2: lockdown profiles and ORA-01219
When you cannot open a database, you will get some users unhappy. When you cannot open multitenant database, then the number of unhappy users is multiplied by the number of PDBs. I like to encounter...
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12c Unified Auditing and AUDIT_TRAIL=DB in mixed mode
Oracle enables some auditing by default, and if you don’t do anything, the tables where it is stored will grow in SYSAUX. Don’t wait to get an alert when it is too late. Everything that fills something...
View Article12cR2: Recover nonlogged blocks after NOLOGGING in Data Guard
You can accept to do NOLOGGING operations on bulk loads or index build according that you do a backup just after, and that your recovery plan mentions how to load the data again in case of media...
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Oracle 12cR2: Online tablespace encryption
By default, all data is visible in the datafiles. Transparent Tablespace Encryption (TDE) can be used to get them encrypted. It requires Enterprise Edition plus Advanced Security Option. Except in the...
View ArticlePurging Unified Audit Trail in 12cR1
When you want to empty a table you have two methods: delete and truncate. If, for any reason (see previous post) the Unified Audit Trail has become too big, you cannot directly delete or truncate the...
View ArticleMisleading wait event names clarified in V$EVENT_NAME
The oracle wait event names were originally implemented for the oracle rdbms developers and are now use by the database users to troubleshoot performance issues. The consequence is that the name may be...
View ArticleOracle 12cR2: changes for login.sql
If you use a login.sql script to set the SQL*Plus environment from your current working directory, you will see that it will not run anymore in 12.2. This is a security feature, and a good occasion to...
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Oracle 12cR2, RAC, Cloud, ACFS, PDB thin clones and asmadmin
In the Oracle Public Cloud, fast provisioning gets all its meaning when creating a RAC database service: in one hour you can get an operational highly available multitenant database. You can even...
View Article12cR2: TNS_ADMIN in env.ora
The network files (sqlnet.ora, tnsnames.ora, lsnrctl.ora) are read by default from ORACLE_HOME/network/admin but you may have several Oracle installations, and want only one place for those files. Then...
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Google Cloud Platform instances and Oracle Database
When it comes to choose a cloud instance to run Oracle Database, you want to be able to run your workload on the minimum CPU cores. This is why in a previous post I measured how many logical reads per...
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Oracle 12cR2 on Windows: Virtual Accounts
Oracle Database 12.2.0.1 is released for Windows, just 2 weeks after the Linux release, and this is a very good news. Let’s see something new you will encounter in the first screens of Oracle 12.2...
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How many members for standby redo logs?
I see lot of databases with two members for redo logs and also two members for standby redo logs. Why not, but when asking I realized that there are some mis-comprehension about it. And what was...
View ArticlePurging Unified Audit Trail in 12cR2
A good thing from 12.2 is that the implementation of Unified Audit Trail has changed a little. It was stored in a weird CLI_SWP$ table but now we have a normal partitioned table named AUD$UNIFIED. In a...
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JAN17 Proactive Bundle Patch + Adaptive Statistics control
If you have to create a new database now (I’m writing this in March 2017) for a migration of OLTP database with minimal risks of regression, I would recommend: The latest patchset of Oracle Database...
View ArticleWhen automatic reoptimization plan is less efficient
11gR2 started to have the optimizer react at execution time when a misestimate is encountered. Then the next executions are re-optimized with more accurate estimation, derived from the execution...
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12cR2 DBCA, Automatic Memory Management, and -databaseType
This post explains the following error encountered when creating a 12.2 database with DBCA: [DBT-11211] The Automatic Memory Management option is not allowed when the total physical memory is greater...
View Article12cR2 DML monitoring and Statistics Advisor
Monitoring DML to get an idea of the activity on our tables is not new. The number of insert/delete/update/truncate since last stats gathering is tracked automatically. The statistics gathering job use...
View ArticleService “696c6f76656d756c746974656e616e74″ has 1 instance(s).
Weird title, isn’t it? That was my reaction when I did my first ‘lsnrctl status’ in 12.2: weird service name… If you have installed 12.2 multitenant, then you have probably seen this strange service...
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SQLcl on Bash on Ubuntu on Windows
I’m running my laptop on Windows, which may sound weird, but Linux is unfortunately not an option when you exchange Microsoft Word documents, manage your e-mails and calendar with Outlook and present...
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