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12.2 Archives - Blog dbi services

Franck Pachot

12cR2 needs to connect with password for Cross-PDB DML

By | Database management | No Comments

In a previous post, I explained that Cross-PDB DML, executing an update/delete/insert with the CONTAINERS() clause, seems to be implemented with implicit database links. Connecting through a database link requires a password and this blog post is about an error you may encounter: ORA-01017: invalid username/password; logon denied This blog post also explains a consequence of this implementation, the big inconsistency of CONTAINERS() function because the implementation is completely different for queries (select) and for…

 
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Franck Pachot

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

By | Database management | 2 Comments

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 week, I tried to…

 
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Franck Pachot

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

By | Database management | No Comments

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 DML. Currently, not all…

 
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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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Franck Pachot

12cR2 RMAN> REPAIR

By | Database management | One Comment

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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Franck Pachot

12cR2 DML monitoring and Statistics Advisor

By | Database management | No Comments

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 rule_id=14;   RULE_ID NAME…

 
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