databases

Phinx joins CakePHP!

These are some really good news – Phinx joins CakePHP family! If you are from a different technology stack and not familiar with these, Phinx is an excellent database migrations tool, which has been used by CakePHP framework for a while now. The two worked great together. Now that they are under the same roof, I’m expecting even more goodies!

We are very excited to announce that Phinx has joined the CakePHP team. The Github project has already been moved to the CakePHP organisation. The project itself will stay MIT-licensed but be gradually transformed into a Cake Software Foundation project. Other great news is that the current way to install and update Phinx remains unchanged.

As you are aware, CakePHP has been using Phinx since 3.0.0 for database migrations. The CakePHP Core team welcomes the opportunity to look after and maintain the project and will now start making changes to bring the code in line with the CakePHP (our) coding standards. As well as cleaning up issues and PR’s soon. We will be following up with our plans for the code and setting roadmaps in the coming weeks.

We welcome Phinx to the CakePHP family and hope to see Rob Morgan, Richard Quadling, Woody Gilk around!

Living Without Atomic Clocks

“Living Without Atomic Clocks” is an interesting article that covers some design bits of distributed systems and CockroachDB (what a name!), especially those related to time precision. This part in particular is the one I’m sure I’ll came back to at some point:

How does TrueTime provide linearizability?

OK, back to Spanner and TrueTime. It’s important to keep in mind that TrueTime does not guarantee perfectly synchronized clocks. Rather, TrueTime gives an upper bound for clock offsets between nodes in a cluster. Synchronization hardware helps minimize the upper bound. In Spanner’s case, Google mentions an upper bound of 7ms. That’s pretty tight; by contrast, using NTP for clock synchronization is likely to give somewhere between 100ms and 250ms.

So how does Spanner use TrueTime to provide linearizability given that there are still inaccuracies between clocks? It’s actually surprisingly simple. It waits. Before a node is allowed to report that a transaction has committed, it must wait 7ms. Because all clocks in the system are within 7ms of each other, waiting 7ms means that no subsequent transaction may commit at an earlier timestamp, even if the earlier transaction was committed on a node with a clock which was fast by the maximum 7ms. Pretty clever.

How to Synchronize WordPress Live and Development Databases

SitePoint runs through a few options that one can use to synchronize WordPress live and development databases. I’ve linked to some of these options before, but it’s nice to have them all conveniently together. The solutions discussed include WordPress-specific tools:

as well as generic tools, such mysqldump, mysqlpump, rsync, and git.

Overall, it’s a pretty complete list of tools. The one I’d like to add though is WP CLI, which allows a great deal of automation when it comes to WordPress, including things like database imports and exports, post and option management, and more.

Gay marriage: the database engineering perspective

Gay marriage: the database engineering perspective is a rather old article on how gay marriage (and other types of marriages) can affect technology, but somehow I missed it for all these years.

It’s interesting from a variety of perspectives – technical, social, and cultural. It’s also somewhat tongue in cheek, yet insightful and thought-provoking. Irrelevant of your views on the subject, I recommend this read. Where else will you find 14 database schema designs trying to solve the same problem.

The legal ramifications of what I’m about to describe are unguessable. I have no idea what rights a civil union like the ones which would be possible below would have, nor do I have any idea what kind of transhuman universe would require so complex a system. This is the marriage database schema to take us up to the thirty-first century, people.

If databases are that difficult to adjust, I can’t even imagine the effort needed for humans…

MySQL 8 is coming

OpenSource.com covers the upcoming release of the MySQL 8.

What happened to 6 & 7?

Years ago, before the Sun Microsystems purchase of MySQL AB, there was a version of MySQL with the number 6. Sadly, it was a bit ambitious and the change of ownership left it to wither. The MySQL Cluster product has been using the 7 series for years. With the new changes for MySQL 8, developers feel they have modified it enough to bump the big number.

The new version brings a whole lot of changes to filesystem organization, indexes, faster ALTER TABLE, and more.