The goal of this article is to to take one query and use the explain facilities of Db2 to walk through it, and then do the same with MySQL, and then show some of the optimizations I might make for the query and why.… Read the restContinue reading »
I’ve spent some time understanding how MySQL structures tables and indexes, and wanted to share what I’ve learned. This is not the structure as created in the
CREATE TABLE or
CREATE INDEX statements, but how that data is generally structured on disk, both logically and physically.… Read the rest
As I’ve been learning the details of MySQL, there have been a lot of similarities with Db2, and a number of differences. Some of those differences have been things I was expecting, while others have been a bit more shocking. If others are making the transition from Db2 to MySQL (using InnoDB) or vice versa, or are supporting both, maybe something here will help.… Read the restContinue reading »
Indexes are magic, right? Add one and magically the performance of a query improves.
Well, not really. Each index has a cost, and thoughtful multi-column indexes will go a lot further than individual indexes. Let’s dig into the details.
What an Optimizer Does
Relational databases require queries to specify what data they want returned with no specification of where that data is on disk.… Read the restContinue reading »
Moving from being a DBA on a proprietary RDBMS for 20 years to working on an open source RDBMS is teaching me a lot of lessons. Many of them are lessons I expected – remembering how and when to ask for help, getting used to not being expected to be the expert on everything, and technical details around how MySQL does things differently.… Read the restContinue reading »
The database conference organization I’ve focused on for most of my career – IDUG (International Db2 Users Group) is not interested in cross-platform content. Despite being a top speaker most conferences, they are not interested in content from me that covers things like transitioning from Db2 to MySQL or technical writing about database concepts.… Read the restContinue reading »
There have been a few times in my career where I have been stunned by something I have seen while at work.
Sometimes it was the good type of stunned. Like the first time first time I observed a truly obnoxiously large workload hit my production database and the database still performed like a champ.… Read the restContinue reading »
I’m a couple of months into working with MySQL, and thought I’d share some resources and thoughts on what I’m learning and what is working. At least half of that time was dedicated to a very in-depth onboarding process that barely mentioned a database at all in about a month of content, so it’s closer to a month in.… Read the restContinue reading »
Many RDBMSes have similar structures and concepts. In this post, I’m going to compare and contrast IBM Db2’s concept of a clustered index and MySQL’s concept of a clustered index.
Index vs. Clustered Index
An index is generally a way of organizing data in a way that it will be quicker to access than scanning through all of a table.… Read the restContinue reading »
I’ve struggled to write this blog entry to appropriately convey all aspects of what I want to say. This is my third attempt, and I finally think it does things justice.
As part of my publicly shared data science journey, I’ve continued to read job postings, even while reasonably satisfied with my current job.… Read the restContinue reading »