Everything our consultants learn while running databases for customers: Oracle, PostgreSQL, SQL Server, MySQL, MariaDB, MongoDB and Delphix. Expect hands-on posts about installation, day-to-day administration, backup and recovery, performance tuning, replication and upgrades.
Last month, I present in the IT-Tage 2017 in Frankfurt am Main, a session about SQL Server 2017 overview. During my session I made a demo on one of the new string T-SQL Commands: TRIM. My demo was very simple but I have also 2 very good questions. Before, I write about these question, I will show you what is…
This post is a demonstration on how to deploy a fully supported Oracle GoldenGate as cluster resources. We are going to use the Oracle Grid Infrastructure Agents, called XAG to integrate the GoldenGate instance within our cluster as a cluster managed resource. This tool is provided by Oracle in the binaries with the release 12c and later but it is…
This is my first blog of this new year and since a while by the way. Indeed, last year, I put all my energy to realign my Linux skills with the new Microsoft’s strategy that opens SQL Server to Open Source world. But at the same time, I did a lot of interesting stuff at customers shops and I decided…
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 when one of the DDL fails on one PDB? PDB$LASTREPLAY In the last post, the C##USER1 common user was created and all pluggable databases…
By Franck Pachot . In multitenant, you can create common Users, Roles, and Profiles. You create them in CDB$ROOT, with the CONTAINER=ALL clause (which is optional because it is the only possible value when connected to CDB$ROOT) but they are visible to all containers. As the goal of multitenant is to avoid to duplicate common metadata to all containers, You…
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 filesystem. However, to ensure that space is reclaimed, we must be sure that Oracle did not leave a process with…
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 transformations to get an efficient execution plan. Here is one new that appeared in Oracle 12cR2: Subquery Elimination when the…
In 2015 I wrote a blog named “All you need to know about Oracle Database licensing with VMware”. This blog generated lots of comments and hopefully helped some DBAs and IT Managers understanding the potential issues that they can face in case of Oracle LMS Audit. In 2 years I made some new experiences related to Oracle LMS audit and…
By Mouhamadou Diaw Oracle 12c introduces moving online datafile. One question we might ask is what about moving datafile online in a dataguard environment. In this blog we will do some tests Below our configuration, we are using oracle 12.2 DGMGRL> show configuration; Configuration – MYCONT_DR Protection Mode: MaxPerformance Members: MYCONT_SITE – Primary database MYCONT_SITE1 – Physical standby database Fast-Start…
By Mouhamadou Diaw The last day I was discussing with one colleague about database flashback for a pluggable database in a dataguard environment. I did some tests and I present results in this blog. Below our broker configuration. Oracle 12.2 is used. DGMGRL> show configuration; Configuration – MYCONT_DR Protection Mode: MaxPerformance Members: MYCONT_SITE – Primary database MYCONT_SITE1 – Physical standby…
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 to perform Oracle deployment of many kind of database architectures you may need like Oracle single instance, Oracle Restart or…
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 with the OTN license agreement, and that makes it not easy to distribute an automated way to build an environment.…
