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.
As more and more customers ask for expertise in Oracle GoldenGate this blog post is the first in a series and outlines how to install Oracle GoldenGate 12c and how to patch it to the latest release on Oracle Linux 7.1 x64. The installation sources (as always) can be downloaded from otn.oracle.com. For the latest patchset you’ll need access to…
By Franck Pachot . In the previous blog post I’ve measured the physical i/o performance, with SLOB. We can run the same with a small size of data and a large buffer cache in order to measure logical reads (LIOs) and CPU performance. What is an OCPU? Except if you are licensed in NUP, you are already used to pay…
Before PostgreSQL 9.5 (which is in alpha2 currently) you could grant access to individual columns of a table to users or roles. A little test script to demonstrate this: (postgres@[local]:5432) [postgres] > select version(); version ————————————————————————————————————– PostgreSQL 9.4.4 on x86_64-unknown-linux-gnu, compiled by gcc (GCC) 4.8.3 20140911 (Red Hat 4.8.3-9), 64-bit (1 row) create table t ( id int primary key,…
By Franck Pachot . Having a database in the cloud is very nice. You add storage with a few clicks. You don’t have to think about the storage type (DAS, SAN, NAS), size of disks, stripe size, SSD, etc. But do you have the performance you expect? I’ve tested I/O in the Cloud that just opened for Europe, so that…
By Franck Pachot . You buy resources on the Cloud, but they are mutualized, thanks to virtualization. Are you sure you have the resources you paid for? When it comes to Oracle databases there are 3 ways to test performances: Run an application, or a simulation of an application, such as the excellent SwingBench from Dominic Giles Run low-level calibration…
Maintenance & Metadata My last chapter is about the maintenance backup/restore, index rebuild/reorg., etc. and the Metadata. I divide my article into 4 parts to be clearer and easier to read: Part I – Principle & Creation Part II – INSERT, UPDATE & DELETE commands Part III – SELECT command Part IV – Maintenance & Metadata SQL Server version/built used…
SELECT command In this article, I present the last command SELECT. I divide my article into 4 parts to be clearer and easier to read: Part I – Principle & Creation Part II – INSERT, UPDATE & DELETE commands Part III – SELECT command Part IV – Maintenance & Metadata SQL Server version/built used for this serie of articles is…
INSERT, UPDATE & DELETE commands After the introduction and the table creation, in this second part, I present the 3 important commands INSERT, UPDATE & DELETE. I divide my article into 4 parts to be clearer and easier to read: Part I – Principle & Creation Part II – INSERT, UPDATE & DELETE commands Part III – SELECT command Part…
Principle & Creation Microsoft create in SQL server 2016 a new feature temporal table, based on the latest edition of the SQL standard: SQL:2011. If you want read more about this standard, click here. I divide my article into 4 parts to be clearer and easier to read: Part I – Principle & Creation Part II – INSERT, UPDATE &…
A couple of weeks ago, I performed a SQL Server audit and my customer talked me about a performance issue he faced only during the login phase of its application. After various exchange of information between my customer and the software editor, they noticed that this problem doesn’t occur when the application and the SQL Server instance are on the…
By Franck Pachot . You have lot of db links between two databases, you think they are not used but want to be sure. It’s not difficult. When doing distributed transactions (which means running a transaction that involves remote databases through db links) the SCN of the database is synchronized. Comparing them can help. But let’s explain that. SCN synchronization…
By Franck Pachot . When we give our trainings (dbi services workshops) we signal our best practices with this logo. It’s our know-how, acquired through experience, consulting, service desk, exchange at events, beta testing, etc. that we share with our customers. Let’s have a look at a few points that we recommend to change if you provision a database with…
