Oracle

Multitenant, PDB, ‘save state’, services and standby databases

By Franck Pachot . Creating - and using - your own services has always been the recommendation. You can connect to a database without a service name, though the instance SID, but this is not what you should do. Each(…)

Migrate Windows VM with more than 4 Disks from VMware to OVM

Suppose you got an OVA image created on VMware and the VM contains more than 4 Disks and you have to migrate this machine from VMware to OVM. As first step you import the OVA into the OVM in(…)

Result Cache: when *not* to use it

By Franck Pachot . I encountered recently a case where result cache was incorrectly used, leading to high contention when the application encountered a peak of load. It was not a surprise when I've seen that the function was called(…)

Testing Oracle SQL online

By Franck Pachot . Want to test some DDL, a query, check an execution plan? You need only a browser. And you can copy-paste, or simply link, your test-case in a forum, a tweet, an e-mail, a tweet. Here is(…)

Explain Plan format

By Franck Pachot . The DBMS_XPLAN format accepts a lot of options, which are not all documented. Here is a small recap of available information. The minimum that is displayed is the Plan Line Id, the Operation, and the Object(…)

Unplug an Encrypted PDB (ORA-46680: master keys of the container database must be exported)

By Franck Pachot . In the Oracle Database Cloud DBaaS you provision a multitenant database where tablespaces are encrypted. This means that when you unplug/plug the pluggable databases, you also need to export /import the encryption keys. You cannot just(…)

Spectre and Meltdown on Oracle Public Cloud UEK – LIO

By Franck Pachot . In the last post I published the strange results I had when testing physical I/O with the latest Spectre and Meltdown patches. There is the logical I/O with(…)

Spectre/Meltdown on Oracle Public Cloud UEK – PIO

By Franck Pachot . The Spectre and Meltdown is now in the latest Oracle UEK kernel, after updating it with 'yum update': [opc@PTI ~]$ rpm -q --changelog kernel-uek | awk '/CVE-2017-5715|CVE-2017-5753|CVE-2017-5754/{print $NF}' | sort | uniq -c 43 {CVE-2017-5715} 16(…)

RMAN debugging during catalog import

In this post I would like to share how I have been able to troubleshoot and solve a catalog import issue using RMAN debug function. As we can see, the error message provided by RMAN is not very helpful. oracle@vmtestoradg1:/home/oracle/(…)

ORACLE 11g to 12c RMAN catalog migration

This is a small migration demo of a 11g catalog (RCAT11G) to a new 12c catalog (RCAT12c). Demo databases environments have been easily managed thanks to DBI DMK tool. oracle@vmreforadg01:/home/oracle/ [RCAT11G] sqh SQL*Plus:(…)