Sometimes I wonder where this whole web development thing is going...I was asked to setup some backup and recovery tools for the BerkeleyDB Java Edition (JE).Hmm... DB... I could probably argue that DB should be dropped from the name if you add Java edition to it. I suppose maybe it's Oracle's plan to drop BerkeleyDB for the newer improved BerkeleyDB Java Edition (JE). Maybe that's why there

Dealing with hierarchies in a relational database is a pest. There's Oracle's CONNECT BY PRIOR, and the SQL standard defines IBM's recursive UNION, but still... wouldn't it be nice if a hierarchy (or even a full-on graph, like social networks have) could just be managed cleanly relationally?

This is something Kim and I have been dabbling with. The engine is called OQGRAPH (OQ for Open Query) now because just graph caused some symbol conflict hassles. Anyway, following is a brief demo of how it works.

First, let's insert some data...

mysql> INSERT INTO gstest (origid,destid) VALUES (1,2),(1,3),(2,4);

Get it back out plain...

mysql> SELECT origid AS node, destid AS edge FROM gstest;
+-------------+
| node | edge |
+-------------+
|    1 |    3 |
|    1 |    2 |
|    2 |    4 |
|    3 | NULL |
|    4 | NULL |
+-------------+

(Hey, notice something? the engine …

I reported "Processlist shows status NULL when server is purging/managing query cache" in April 2007, while I was still in MySQL support engineering. This issue actually made tracking down other bugs and customer issues take longer. About a year later, MySQL 6.0 codebase apparently has the progress info. By the way, we are essentially talking about a one-line fix, adding something like thd->proc_info="Flushing table from cache"; at the appropriate spot.

In the mean time, three bugfix meetings have spent time on this item (judging by the tags), those are meetings where MySQL (re-)prioritises some bugs for fixing. That's an awful lot of time to waste euh spend on this thing. The bug entry itself is still open as "feature request", and I presume MySQL support and bug engineers are still wasting time due to the insufficient reporting in 5.0 and 5.1. In the …

We were doing MySQL Performance evaluation on TPC-H queries for the client and they kindly allowed us to publish results which are very interesting.
This is obviously not audited TPC-H run, and it can’t be because we used MyISAM tables which are not ACID complaint. Plus we only measured Power to keep things simple.

We tested 10G and 100G data sets which was CPU bound and IO bound box on the Dell 2950 box w 16G of RAM which we used for testing. Even though box had 8 cores it is little use for MySQL as only one query is ran concurrently, same can be told about 8 hard drives which this box had.
MySQL Also was very slow running some queries so we changed scripts a bit to kill extremely long running queries to get results for others this means we can’t really get a valid TPC-H result from MySQL,though at least we get to see performance of individual queries.
We also packaged the toolset we used for benchmarks so you can …

It’s been six weeks since the completion of the acquisition of MySQL by Sun Microsystems. In this time, on the MySQL News and Press Releases there has only been one (1) Press Release here.
In the six weeks between the announcement and completion of the acquisition MySQL made ten (10) Press Releases, and the six weeks preceding this including the Christmas break there was (six) Press Releases.

On the Sun Press Releases in this period there has been twenty three (23), but just the same one MySQL specific. …

I’ve been seriously swamped in these last few weeks. Relocating (from Melbourne to Kuala Lumpur) has been interesting. Not to mention that all the work that’s still around…

I should mention that I am now Sun, having signed all paperwork a few weeks back. It just dawned on me when I picked up my ID card today from the Sun KL offices. No email address yet, but our @mysql.com addresses will continue to work (they’re on my business cards).

Which brings me to the fact that I am also sporting new business cards (no direct-line number, yet - still waiting on its creation), and they have an interesting logo on the back!

MySQL/Sun logo At the conference, if folk are still giving out “older” MySQL cards, keep them - they’re collector’s items now. Me? I’ll be bringing my new ones ;)

Technorati Tags: sun, …

A session at the MySQL Conference 2008 that I’d have loved to attend, would have been the Adopting and Adapting OSS at Shinsei Bank. As a case study, Shinsei Bank in Japan is a great MySQL customer and use case - they’re a bank. A pretty large bank…

Sadly, the session has been cancelled. Never fear, because at 4.25pm on Wednesday, the 16th of April 2008, there are seven other great sessions.

If you’re interested in web security, then look no further than Eli White’s talk titled Help, My Website Has Been Hacked! Now What? Eli works at Digg, and might have some invaluable practical advice for you.

If you’re more the systems administrator, you …

Well at least your MySQL database world.

As Paul eluded to, PrimeBase Technologies has a project to provide synchronous replication for MySQL in a High Availability environment. It is more then an idea, there is a plan.

Is it possible?
What are the use cases?
How can you use it?
Would you use it?

Some input to date. We need these questions and more, and we seeking more input for discussion.

Unfortunately the opportunity to hear any input during a presentation is left to the last day of the conference, so we have created a BoF session on Tuesday night for a round table discussion if necessary. We encourage people to bring specific cases and situations for feedback, the reasons why MySQL Replication, MySQL Cluster, DRBD/HeatBeat or any other solution does not satisfy your needs, and what …

The problem: You’re creating an (InnoDB) table with foreign key constraints:

CREATE TABLE a (
  b INT NOT NULL,
FOREIGN KEY b REFERENCES c(d)
) ENGINE=InnoDB;

and MySQL throws an ERROR 1005 (HY000): Can't create table ... (errno: 150)

In 95% of the cases, this means you need to create an index on c(d):

ALTER TABLE c ADD PRIMARY KEY (d)

Just a subjective observation, been through a few bookstores this arvo (sorry, afternoon - Australian ;-) and I tend to do a quick check of the computer section to see what MySQL books are there.
It appears that over the last year or perhaps even longer, fewer new MySQL books have come out, and fewer MySQL books hang around on the shelves. Less interest, I don't know.
O'Reilly's annual report on the book market probably has some insight into this but it's late in the evening here so I'm not going to delve into that right now.
Anyway, it's quite possible that the market is fairly saturated, and there are some good books out there covering most features and uses. So all that remains is new functionality, and there hasn't really been that much which warrants writing a completely new book about it. Stored procedures was probably the last such instance. Like, partitioning is interesting, but not for a full book. Falcon, diddums (at …