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.
PostgreSQL supports tables up to 32TB. Do you want to be the one responsible for managing such a table? I guess not. Usually you start to partition your tables when they grow very fast and consume more than hundreds of gigabytes. Can PostgreSQL do this? Do you you know what table inheritance is? No? PostgreSQL implements partitioning by using table…
By Franck Pachot . Today at #ukoug_tech16 12:30 in hall 11A I’ll talk about Statistics Gathering Best Practice & 12cR2 Statistics Advisor Rather than taking the Optimizer Statistics Advisor rules one by one I’ll show the things to take care (some people may call it best practices) when gathering statistics and they mention the Statistics Advisor Rule. If you need…
Why should you migrate? If your current MySQL database does not offer some needed functionnalities according to your business as: – more security – more high availibilty options (hot standby) – Strong Data Warehouse capabilities If you want to consolidate the number of different instances (Postgres, MySQL, MS-SQL,…) If you want to reduce administrative costs by using fewer database platforms…
During the last MVP summit, we had some interesting discussions about availability groups with the SQL Server team and I remember someone asked for managing scenarios like Oracle cascaded destinations and the good news is that SQL Server 2016 already addresses this kind of scenario with distributed availability groups. For example, let’s say you have to manage heavily reporting activity…
By Franck Pachot . Today at UKOUG TECH16 conference I’m presenting the internals of the new multitenant architecture: 12c Multitenant: Not a Revolution, Just an Evolution. My goal is to show how it works, that metadata links and object links are not blind magic. Here are the links to the blog posts I’ve published about multitenant internals. The dictionary separation,…
Today we’ll continue this series with another topic: What does PostgreSQL provide when it comes to server programming, that is: Writing functions and triggers to support your application? In Oracle you can either use PL/SQL or Java, in MariaDB you can use stored procedures written in SQL, MS SQL Server provides Transact SQL and with DB2 you can write stored…
By Franck Pachot . In short, when have statistics gathered in 11.2.0.3 but the query is now running with the 11.2.0.4 optimizer, you may have wrong cardinality estimation on histograms, leading to sub-optimal plans. I had a table with a flag that has two values ‘Y’ and ‘N’ with even distribution between them. It’s a good case for frequency histograms.…
By Mouhamadou Diaw In this blog we will talk about how to do a switchover and how to do a failover. We suppose that dbvisit is already installed and that a standby database is already configured. Our instance is named DBPRIMA. Switchover SWITCHOVER is the fact to change database role. The primary becomes the standby and the standby becomes the…
By Mouhamadou Diaw The new version of Dbvisit standby is now released. In this blog we are going to see how to install dbvisit 8 and how to create a standby database. For the installation after downloading the software, just uncompress it and then run the install-dbvisit command under the installer directory. The installation process is divided in 2 parts.…
From time to time it is very useful that you can generate the DDL commands for existing objects (Tables, Indexes, whole Schema …). In Oracle you can either use the dbms_metadata PL/SQL package for this or use expdp/impdp to generate the statements out of a dump file. What options do you have in PostgreSQL? Note: We’ll not look at any…
By William Sescu I have setup a DataGuard environment and followed the instructions from Oracle to create the Standby Redo Logs. The Standby Redo Logs have to be the same size as the Online Redo Logs. If not, the RFS process won’t attach Standby Redo Logs, and you should have at least one more of the Standby Redo Log Group…
By Franck Pachot . Oracle Transparent Data Encryption is available without option on the Oracle Public Cloud: Standard Edition as well as Enterprise Edition (EE, EE-HP EE-EP, ECS). More than that, the DBaaS enforces TDE for any user tablespace even when not specifying in the CREATE TABLESPACE. It you are not familiar with TDE key management (wallets) then you have…
