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12.2 Archives - Blog dbi services

Franck Pachot

12cR2: TNS_ADMIN in env.ora

By | Database Administration & Monitoring | No Comments

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 links from the ORACLE_HOME…

 
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Franck Pachot

Oracle 12cR2, RAC, Cloud, ACFS, PDB thin clones and asmadmin

By | Cloud, Database Administration & Monitoring | No Comments

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 create it in Data Guard for Disaster Recovery. Now, Oracle is pushing ACFS to store the datafiles rather than direct ASM. Especially in multitenant because a great feature is thin cloning: CREATE PLUGGABLE DATABASE AS SNAPSHOT COPY. However, I encountered an error when…

 
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Franck Pachot

Oracle 12cR2: Online tablespace encryption

By | Database Administration & Monitoring | One Comment

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 Oracle Cloud when it is available – and mandatory – in all editions. And we can foresee that security policies will be enforced in the future years, by law or because companies realize their files can be stolen. This means that lot of databases…

 
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Franck Pachot

12cR2: Recover nonlogged blocks after NOLOGGING in Data Guard

By | Database Administration & Monitoring | No Comments

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 recovery. With a standby database, we usually force logging because we want redo to be generated for all operations in order to ship it and apply it on standby database. 12.2 brings a new solution: do nologging operations,…

 
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Franck Pachot

12cR2 real-time materialized view (on query computation)

By | Database Administration & Monitoring | 2 Comments

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, aggregates, and see it as one table. It has all advantages of a table, as it is stored in one segment, can be indexed, partitioned, have constraints, be compressed, etc. It looks like indexes as it stores data redundantly,…

 
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Pierre Sicot

UKOUG Super Sunday

By | Database Administration & Monitoring | No Comments

Today at the UKOUG Super Sunday in Birmingham, I had the opportunity to assist at interesting conferences. The first presentation was about Oracle RAC internals and its new features in version 12.2.0.1 on Oracle Cloud. The main new features concern the cache fusion, the undo header hash table, the leaf nodes, and the hang manager. In 12c release 2 in a RAC environment, the cache fusion automatically chooses an optimal path; the cache fusion collects…

 
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