Oracle

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(…)

Automate OVM deployment for a production ready Oracle RAC 12.2 architecture – (part 02)

In this post we are going to deploy a R.A.C system ready to run production load with near-zero knowledge with R.A.C, Oracle cluster nor Oracle database. We are going to use the “Deploy Cluster Tool” which is provide by Oracle(…)

Oracle docker image from docker store

By Franck Pachot . Did you notice that each time you want to download the Oracle binaries from the OTN website (for non-production usage) you have to click on the "Accept License Agreement"? This is because you have to agree(…)

Naming of archivelog files with non existing top level archivelog directory

In Oracle 12.2 an archive log directory is accepted, if top level directory does not exist: oracle@localhost:/u01/app/oracle/product/12.2.0/dbhome_1/dbs/ [DMK] ls -l /u02/oradata/DMK/ total 2267920 drwxr-xr-x. 2 oracle dba        96 Dec  6 05:36 arch ... Now database accepts(…)

Transfer redo in async-mode to the Gold/Master copy of the Production DB for ACFS snapshots

If you store your databases on the cluster filesystem ACFS you may use the provided Perl-script gDBClone from OTN to clone databases or create snapshot databases. It is an interesting approach to create clones from the Production DB(…)

impdp logtime=all metrics=y and 12cR2 parallel metadata

By Franck Pachot . A quick post to show why you should always use LOGTIME=ALL METRICS=Y when using Data Pump. Just look at an example showing the timestamp in front of each line and a message about each task completed(…)

12c Multitenant Internals: compiling system package from PDB

By Franck Pachot . When I explain the multitenant internals, I show that all metadata about system procedures and packages are stored only in CDB$ROOT and are accessed from the PDBs through metadata links. I take an example with(…)

Unstructured vs. structured

By Franck Pachot . The title of this blog post was: "Tracing DBMS_RCVMAN for reclaimable archivelogs" until I started to write the conclusion... In a previous post I mentioned that there's a bug with archivelog deletion(…)