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Oracle Team

random “ORA-01017: invalid username/password” in 12cR2

By | Database management, Oracle | 4 Comments

By Franck Pachot . Since 12cR2 is out, we give our 12c new feature workshop with hands-on exercises on 12.1 and 12.2 releases. When I gave it last month, I had a small problem when doing demos: sometimes the connections as sysdba failed with “ORA-01017: invalid username/password”. It was at random, about one every 5 login attempts and I was sure that the password did not change. As I give another of this training next…

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Oracle Team

12cR2 Cross-container DML – insert into container()

By | Database management | No Comments

By Franck Pachot . Multitenant has been introduced in 12.1.0.1 with the goal to share resources but isolate data. However, having all PDBs in the same root may be convenient to manipulate data in multiple PDBs. In the first patchset, 12.1.0.2, a way to query cross-container has been introduced for the CDB administrator to see data in other containers. In the second release, 12.2.0.1, this goes further with the introduction of Application Containers and cross-PDB…

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Joël Cattin

Oracle 12cR2 : Optimizer Statistics Advisor

By | Database Administration & Monitoring, Database management, Development & Performance | No Comments

The Optimizer Statistics Advisor is a new Advisor in Oracle 12.2. The goal of this Advisor is to check the way you gather the statistics on your database, and depending on what is found, it will makes some recommendations on how you can improve the statistics gathering strategy in order to provide more efficient statistics to the CBO. This Advisor is also able to generate remediation scripts to apply the statistics gathering “best practices”. The…

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Oracle Team

12cR2 RMAN> REPAIR

By | Database management | One Comment

By Franck Pachot . Do you know the RMAN Recovery advisor? It detects the problems, and then you: RMAN> list failure; RMAN> advise failure; RMAN> repair failure; You need to have a failure detected. You can run Health Check if it was not detected automatically (see https://blog.dbi-services.com/oracle-12c-rman-list-failure-does-not-show-any-failure-even-if-there-is-one/). In 12.2 you can run the repair directly, by specifying what you want to repair.

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Oracle Team

12cR2 DML monitoring and Statistics Advisor

By | Database management | No Comments

By Franck Pachot . 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 it to list and prioritize tables that need fresh statistics. This is for slow changes on tables. In 12.2 we have the statistics advisor that goes further, with a rule that detects volatile tables: SQL> select * from V$STATS_ADVISOR_RULES where…

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Oracle Team

12cR2: TNS_ADMIN in env.ora

By | Database Administration & Monitoring | No Comments

By Franck Pachot . 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 you can use TNS_ADMIN environment variable. But are you sure that it is always set when starting the database? the listener? the client? They must be consistent (see https://blog.dbi-services.com/oracle-12cr2-plsql-new-feature-tnsping-from-the-database/). Then what we do for the cases where TNS_ADMIN is not set: define symbolic…

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