For my newest ipython-sql trick, I needed to compare some queries run across different databases. How hard would it be to get side-by-side results into tidy IPython Notebook output?
Not hard at all, it turns out, if you're willing to violate basic principles of human decency.
That's an itty-bitty image, (more...)
After getting %sql magic for IPython working, my next big goal was to figure out how to get those results into Pandas.
Er, OK, not such a big goal. Even with zero Pandas experience, it took about five minutes of skimming the first page of documentation to figure out:
Inspired and informed by discussions with the IPython developers at PyCon 2013, I've released ipython-sql, a %sql magic for IPython.
With this, I really think the IPython Notebook will become the most amazing database tool ever. In fact, virtually every computing problem will become a lot more workable when (more...)
When to consider sharding a MySQL database
Why should you not just design your applications from the start to account for data sharding? Sharding a database, that is horizontally partitioning tables among multiple databases, creates an added level of complexity that is not desirable in an application. However, there are times when sharding is required to maintain acceptable performance. So when is the right time to shard your database?
When to consider sharding a MySQL database Why should you not just design your applications from the start to account for data sharding? Sharding a database, that is horizontally partitioning tables among multiple databases, creates an added level of complexity that is not desirable in an application. However, there are times when sharding is […]
This entry and my next will be a little different from what I normally write. This info comes from some research I did recently into MySQL.
The Three Major Areas of Difference Between MariaDB and MySQL
An unresponsive web site is as good as asking your customers to leave. According to surveys, almost 50% of web users expect a page to load in less than 2 seconds, and 4
The MySQL documentation section has always had this Topic Guides page containing links to the docs for the various MySQL Connectors -- the official database drivers for various languages and programming technologies. That is the most convenient way to get the information for each Connector in PDF form, rather than downloading the entire Ref Man PDF. For HTML, it was more of a shortcut, because
Back-story: A developer came to me and wanted explanation for a weird behavior in MySQL. They inserted a record (to InnoDB table), committed, and after receiving a message (on another application) tried to read that inserted record immediately, but the newly inserted record was not found. Problem only happened in production, but not always (quite frequently).
After comparing the MySQL parameter files between production and development environments I discovered that in production autocommit was disabled to make MySQL behave more like Oracle. This setting was removed from development after we rebuilt the environment (to use multiple MySQL instances with Oracle (more...)
As every year the DOAG (German Oracle User Group) Conference will take place Nürnberg/Germany from the 20th November until 22nd November 2012.
The Call for Papers is already open and ends on 30th June 2012:
German Link: http://www.doag.org/de/events/konferenzen/doag-2012/fuer-referenten.html
English Link: http://www.doag.org/en/events/konferenzen/doag-2012/fuer-referenten.html
Once again, I (more...)
This is THE
MySQL performance book. Period!
Every chapter is very well crafted, with a precise balance between theory and practice, and full of invaluable nuggets, sometimes transcending the MySQL arena and applicable to any database!
Such cases are Chapter 2-Benchmarking MySQL and Chapter 3-Profiling Server Performance, very solid foundations for the reading ahead.
All over the text, authors propose tools, examples of use and proven diagnostic techniques, that will greatly improve your performance firefighter skills and enhance your knowledge of MySQL internals. Nevertheless, what I liked the most from this book is taking into (more...)
Interesting take on what managers are thinking: http://quickbase.intuit.com/blog/2012/01/09/10-things-your-boss-isnt-telling-you/
I've been doing lately quite many database clustering implementations; Oracle RAC and since we have many MySQL instances in production, had to find a good way to make MySQL instances highly available also.
One good solution for this is managing MySQL instances with clusterware and since we are planning to use Oracle RAC on Oracle Enterprise Linux anyway, then Oracle Clusterware is an excellent candidate for this task. Also... Oracle Clusterware is included with Oracle Enterprise Linux at no additional charge.
Requirements I had:
- Multiple MySQL instances running in the same cluster, in case of node failure affected MySQL instances (more...)
After 30 years of Oracle, I've found myself using MySQL recently. I came across a little thing that surprised me. I'm by no means the first to trip over this - I found this 2006 post from Peter Zaitsey
on the same topic.
MySQL lets you write a group by statement that references columns that aren't in the group by, and aren't aggregates. For example:
mysql> select table_name, column_name, count(*)
-> from information_schema.columns
-> where table_schema = 'information_schema'
-> group by table_name
-> limit 5;
| table_name | column_name | count(*) |
| CHARACTER_SETS | CHARACTER_SET_NAME | (more...)
There was an interesting index related performance problem on Stack Overflow recently. The problem was to check an input string against a table that holds about 2000 prefix patterns (e.g.,
LIKE 'xyz%'). A fast select is needed that returns one row if any pattern matches the input string, or no row otherwise.
I believe my solution is worth a few extra words to explain it in more detail. Even though it’s a perfect fit for Use The Index, Luke it’s a little early to put it as an exercise there. It is, however, a very good complement (more...)
The InnoDB Plugin manual is now available on the MySQL web site.
I've been pretty quiet lately, because I'm in a transitional period. After 10 years on documentation for Oracle Database and other enterprise server products, I'm switching to the InnoDB group that already works with MySQL. New development environments, new customers, it's an exciting time!A decade seems to be the right timeframe for me. It was 10 years at IBM before that. Check back in 2019, I'm
In Europe, many people love Open Source with its connotations of sharing and village co-operatives. On the other hand, many Europeans don’t like the big, successful American companies (witness the ritual McDonalds-bashing).
This emotional preference for Open Source to big American companies is why the EU competition authorities have decided (more...)