How to verify if a slave running in MySQL 5.7

Introduction Most people know that you can use SHOW SLAVE STATUS to verify if a slave is running in MySQL. Most people ...

Monitoring apache Cassandra metrics with Graphite and Grafana

1. Overview Despite the fact that Apache Cassandra provides a large number of metrics through the popular Metrics ...

Oracle E-business suite: virtual host names solution for R12.2

You have seen me rant about Oracle's provided virtual hostname solution before. If you have not, check it out here. In ...

SharePlex replication between two instances on the same host

Several days ago I was asked a question about SharePlex and should verify behaviour before providing the answer. I had ...

Oracle Database 12c: PSUs vs database proactive bundle patches

Background When it comes to performing quarterly patches to the Oracle database the options used to be pretty straight ...

Oracle service secrets: group and filter

At the KSCOPE16 conference in Chicago I recorded a two minute tech-tip with Bob Rhubart of OTN about adding services to ...

Things to consider when deciding on a primary key for your INNODB table

When it comes to schema design, one of the more common issues I see for INNODB tables is in the selection of a primary ...

Properly removing users in MySQL

Context Removing users in MySQL is an easy task, but there are some drawbacks to check carefully before dropping a ...

Truncates and sequences replication in Oracle GoldenGate

We use the terms DDL and DML in our DBA life with Oracle all the time. The first stands for Data Definition Language ...

What's eating my database? Where to focus performance efforts using Oracle AWR

Defining the Gold Standard: Average Active Sessions (AAS) Traditional methods would include looking at CPU, load and ...

ASM 12c : how to rename a Diskgroup

The first time I was asked to rename a diskgroup, I thought that it would be a trivial operation, but what should be an ...

An effective approach to migrate dynamic thrift data to CQL, part 1

1. Introduction Recently Pythian's Cassandra team worked on one customer's request to copy data of several Cassandra ...

Analyze index validate structure - the dark side

Recently, a co-worker encountered a significant performance hurdle after a database upgrade. The plan included ...

Custom MySQL statistics with collectd

Even though collectd has a MySQL plugin, you may want to collect other statistics, not included with the plugin or even ...

Exposing Innodb internals via system variables: Part 2, I/O (structure and logs)

Introduction This is part two of a five part blog series to explore InnoDB internals by looking at the related tunable ...

Exposing Innodb Internals via System Variables: Part 1, MemoryExposing Innodb Internals via System Variables

Introduction A couple of months ago I decided to give myself a refresher on the mechanics of InnoDB. Having a high ...

DECIMAL columns and a non-expected replication error

ASM disk group just will not mount

I recently had an issue involving a damaged ASM disk group. Each time an attempt was made to mount the disk group it ...

ASMCMD> a better DU, version 2

Benefits of ASMDU A while ago, I posted a better "du" for asmcmd . Since then, Oracle 12cR2 beta has been released but ...

Creating an external slave for a live AWS Aurora Instance

Overview When working with Amazon AWS Aurora, there are some steps to consider when trying to get data out of an active ...

The getMOSPatch V2 is here!

A while ago I created a Bash script called getMOSPatch.sh. Its purpose was to allow downloading Oracle patches directly ...

How to Install a brand new Exadata X5 (part 2)

Now that all the prerequisites have been performed in Part 1, we can now jump in the Exadata installation procedure ...

GoldenGate 12.2 big data adapters: part 4 - HBASE

This is the next post in my series about Oracle GoldenGate Big Data adapters.

Exposing Innodb Internals via system variables: part 4, concurrency

Introduction This is part four of a five part blog series to explore InnoDB internals by looking at the related tunable ...

Exposing Innodb internals via system variables: part 3, I/O (table data)

Introduction This is part three of a five part blog series to explore InnoDB internals by looking at the related ...

How to install a brand new Exadata X5 (Part 1)

When you buy an Exadata machine, you can ask Oracle to proceed with the installation or let some brilliant DBAs like ...