Oracle

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:(…)

Spectre and Meltdown, Oracle Database, AWS, SLOB

By Franck Pachot . Last year, I measured the CPU performance for an Oracle Database on several types of AWS instances. Just by curiosity, I've run the same test (SLOB cached reads)(…)

Running the Oracle Client on a Raspberry Pi

What are the possibilities to use a Raspberry Pi computer as an Oracle client? Besides other things I’ll show a possibility in this Blog to run the fat/thick Oracle Client on a Raspberry Pi! REMARK: All examples below(…)

Keep your orapw password file secure

By Franck Pachot . This is a small demo I did when I've found a database password file (orapw) lying around in /tmp with -rw-rw-rw- permissions, to show how this is a bad idea. People think that the orapw file(…)

12c Multitenant internals: PDB_PLUG_IN_VIOLATIONS

By Franck Pachot . In the previous post https://www.dbi-services.com/blog/12c-multitenant-internals-pdb-replay-ddl-for-common-users I've done some DDL on a common user to show how this is replayed later for PDBs that were not opened at that time. But what happens(…)

12c Multitenant internals: PDB replay DDL for common users

By Franck Pachot . In multitenant, you can create common Users, Roles, and Profiles. You create them in CDB$ROOT, with the CONTAINER=ALL clause (which is optional because it is the only possible value when connected to CDB$ROOT) but they are(…)

Drop PDB including datafiles may keep files open

By Franck Pachot . I like that Oracle drops the datafiles from the operating system when we remove them from the database (with drop tablespace or drop pluggable database) because I don't like to have orphean files remaining in the(…)

12cR2 Subquery Elimination

By Franck Pachot . More and more we can see crazy queries generated by ORM frameworks or BI query generators. They are build to be easily generated rather than being optimal. Then, the optimizer has to implement more and more(…)