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.
By Mouhamadou Diaw Last day Franck and me were discussing about OCR backup Let’s take a 2 nodes RAC. We can see that OCR backup is automatically done by oracle in only one node on local (with a certain frequency every day, every week and every 4 hours)) [oracle@racsrv2 ~]$ /u01/app/12.1.0.2/grid/bin/ocrconfig -showbackup 1 2 3 4 5 6 7 8…
The just released version of EDB Postgres Advanced Server 9.5 introduces profiles very much the same as in Oracle. Lets have a look at it. As in Oracle there is a default profile: (enterprisedb@[local]:5445) [postgres] > x Expanded display is on. (enterprisedb@[local]:5445) [postgres] > select * from edb_profile; -[ RECORD 1 ]———–+——– prfname | default prffailedloginattempts | -2 prfpasswordlocktime |…
MongoDB is an open source NoSQL database management system document-oriented. MongoDB allows the manipulation of structured and unstructured data. It is schema-less and can be used to store a large data volume. This blog is explaining the main principle of the DBMS. MongoDB stores data in documents. These documents are stored in BSON types, the JSON binary format. Actually, we…
Dear IT colleagues, We regularly have to read log file contents either to understand software functioning or for debugging purpose. Most of the time we access same log files located in same servers. It is very painful to login every time, then lookup and extract relevant traces for a particular case under investigation. On top of that, especially on some…
After my first two blogs about cloud witness and domain-less dependencies features shipped with Windows Server 2016, it’s time to talk about another pretty cool feature of the WSFC : site awareness that will also benefit to our SQL Server FCIs and availability groups. But before to talk further about the potential benefits of this new feature, let’s go back…
Some days ago EnterpriseDB released EDB Postgres Advanced Server 9.5. As usual this release contains all new features that have been introduced with PostgreSQL 9.5 plus the additions that are documented in the release notes. Some time ago I blogged on how to install the 9.4 release. In this post I want to check if anything changed in the installation…
In the last posts (1, 2, 3, 4, 5) I looked at PostgreSQL in Amazon RDS. Another option you have if you want to go to the cloud is to use the The Postgres Plus® Cloud Database offered by EnterpriseDB. I will not go through the whole setup here as this is described in detail here. So once you went…
By Franck Pachot . Yesterday I was giving my ‘Interpreting AWR Reports’ Prezi at Oracle Midlands. There is a point where I explain that I always check the ‘Captured SQL account for …% of Total DB Time (s)’ in order to know whether I’ll get all details in the report or not. There are two main reasons why the most…
In PostgreSQL every database contains the public schema by default. Every user that gets created and can login is able to create objects there. Here is a little demo: I’ll create a new user named u1 which is allowed to login. No additional privileges are granted: postgres=# create user u1 login password ‘u1’; CREATE ROLE postgres=# c postgres u1 You…
Usually I advice to build PostgreSQL from source as it gives the most flexibility. Another option is to use the official yum repositories. There is one repository for each supported release of PostgreSQL and most of the common RedHat based Linux distributions are listed: CentOS, Oracle Linux, RedHat, Fedora, Scientific Linux and even Amazon Linux. Currently PostgreSQL 9.6 is in…
By Franck Pachot . Do you know the optimizer_features_enable parameter? What do you think about it? Good or bad to use it? If I tell you to set optimizer_features_enable parameter=11.2.0.4 when you upgrade to 12c, do you think it’s a very safe decision, or totally insane to upgrade and set behavior to previous version? It’s not an underscore parameter, you…
By Franck Pachot . Here is a query I use when I’m on a system that has Diagnostic Pack (ASH) but no tuning Pack (SQL Monitor). It displays the execution plan with dbms_xplan.display_cursor and adds the % of ASH samples in front of each plan operation. Here is a small output example. Usual dbms_xplan output but showing the most active…
