It's seems that Mac OS X has become the OS of choice for many people that wanted to get away from Windows or got too frustrated with Linux on the desktop. MySQL has been ported to OS X a long time ago and is even shipped as a component of OS X Server. The Apple Developer Connection now has a nice article about using and developing MySQL on OS X, including many quotes from Brian Aker.

Hmm. Planet MySQL was close to unreadable for me this morning. Also, I had a technical discussion on writing style with a colleague just a few weeks ago, so I might as well take what I explained to him and put it into a form suitable for Planet MySQL. Please note that this is how I see things. This may or may not coincide with Arjen's view or the view of MySQL AB.



If you write blog entries for a blog that is being picked up by a planet, you are writing for a larger audience that for your own blog, and that audience may have other goals and intentions than regular readers of your blog. Here are a few things to keep in mind:

Regular readers of your blog are coming specifically to you because they share a lot of interestes with you regarding the topics you cover. You can go into a lot of depth and you can assume a lot of context.

When your blog is being picked up by a planet, things are …

Views are a great feature which is available as of MySQL 5. A view can be seen as a named and persistently stored SELECT expression. After defining the view it can be referenced just like a table in other queries.

Metadata for MySQL Views can be queried using the TABLES and VIEWS tables from the information_schema. This can be very helpful when maintaining or developing views.

However, this metadata would be even more valueable if it would provide …

I was writing this in an email to a co-worker today, could possibly interest people in the outside world as well. It’s a good idea to look at the source at the same time as reading this :)

In ha_ndbcluster::write_row(byte*),

if (table_share->primary_key != MAX_KEY)
{
/*
* Increase any auto_incremented primary key
*/
if (has_auto_increment)
{
THD *thd= table->in_use;

m_skip_auto_increment= FALSE;
update_auto_increment();
/* Ensure that handler is always called for auto_increment values */
thd->next_insert_id= 0;
m_skip_auto_increment= !auto_increment_column_changed;
}
}

We set next_insert_id to 0 so that in handler::update_auto_increment() we end calling the handler and never doing it just inside the server.

The handler function that we end up in is: …

In sqlcmd, you can connect to a different server by this command:

:connect MyServer

The above command will attempt to use integrated / Windows Active Directory authentication. To use traditional Sql Server authentication, use this instead:

:connect MyServer -U MyLogin

You can do the same kind of thing in Oracle Sql Plus by using this command:

conn[ect] MyLogin@OracleSID

For mysql command line, use this:

connect -h MyServer -u MyLogin -p

That is assuming that you are allowed to login to the MySql server from whereever you are now.

DUBLIN, Ireland -- MySQL AB is seeing increased growth and momentum in EMEA, resulting in further expansion of its European corporate sales office in Dublin, Ireland. This is a result of unprecedented demand for MySQL database software in Europe. Recent major European customer wins for MySQL include Afnor, Alcatel, neckermann.de, Nokia, Pricer, Sagem Monetel, SEAT Pagine Gialle, Shunra, United Nations' FAO, Virgin Mobile, Waitrose, and Ya.com.

InnoDB is a special case among MySQL storage engines because they have clustered indexes, which means surrogate keys have to be treated differently in InnoDB. This article gives a quick overview of clustered indexes, and explains why they make it even more important to do careful analysis before making decisions about surrogate keys on InnoDB tables. Overview of clustered indexes in MySQL A clustered index is just like any other index, except the index holds the data itself, in index order.

For those of you who want to hear me read this instead of having to do so yourself (no hyperlinks), click here for .ogg and here for .mp3.

I migrated the blogs’ database and code from moonunit to avenger, both of which run Debian Sarge. Y’all should now notice a vast improvement in throughput. The ISP that Moonunit sits on should also see a large decrease in traffic.

Today, I added a campaign to raise funds for hosting. If you have any extra funds, please help me with colocation costs. It’s expensive and y’all use up a bunch of bandwidth. If you find this site …

Let’s look into selectivity, as this is an important topics when looking at index performance. (Oooh, I said “performance”, watch everyone’s ears perk up!).

This will probably answer the questions “Why isn’t MySQL using my index?” or “Why is my query so slow when I have an index on it?”

Selectivity describes how different values of a field are. It is a number from 0-1, although you can also think of it as a percentage. A value of 1, or 100%, means that each value in the field is unique. This happens with UNIQUE and PRIMARY keys, although non-unique fields may have a selectivity of 1 — for example, a timestamp value in a not-often-used table.

To calculate this, you take the total number of DISTINCT records and divide by the total number of records.

My company has a large Users table, so I grabbed some statistics off of that:


+----------+
| …

Yet again, the Boston MySQL Meetup was a success. Larry Stefonic, Senior Vice President, Worldwide OEM & Embedded Sales and President, MySQL K.K. (Japan) was on hand to witness the event. There were 15 people total at the meetup, which is our lowest yet, but I’ll get to why I was not disappointed at all later on.

However, the topic was advanced: “Measuring MySQL Server Performance for the Sensor Data Stream Processing” presented by faithful MySQL Meetup attendee Jacob Nikom, from MIT Lincoln Labs. (he’s been to every meetup!)

And I was very impressed with the questions folks asked of Jacob — the group was half the size of what we usually are, but we were all fully engaged. I’m very proud of the MySQL group! We have a diverse range of skills and I’m glad we can accomodate all of them.

Next month’s topic will be “Storing images in a database,” which was pushed out of the way in April to make room for Jay …