There are these everlasting misconceptions about MyISAM's
capabilities, many documents and articles "out there" just state
that it's merely suitable for reads. Well, I'm afraid that's an
over-simplification. Quite unfortunate, since users could
explicitly benefit from MyISAM strong points for quite a few
other situations too. Just remember that MyISAM does not have
transactions/rollback, so if you need that, you'll want to use
another MySQL storage engine like InnoDB, NDB Cluster, PBXT,
Solid, or soon Falcon. That's fine. Whatever suits best.
So what's the deal with MyISAM? There's multiple aspects to the
story. First of all, it's important to realise that the
table-level locking comes in different flavours. There's not just
one single type of lock, instead we see READ (shared) locks for
selects, and WRITE (exclusive) locks for write operations. And
there's a special READ LOCAL lock to allow inserts during
selects. By the way, MySQL …
ExitCertified Corporation of Ottawa, Canada, is pleased to announce that they have been selected by MySQL AB to be the first Authorized MySQL Education Center (AMEC) partner for Canada, offering certified MySQL education across the country. Courses will be offered on MySQL 5.0, the latest version of the world?s most popular open source database.
By tim
Paul Graham recently wrote a couple of thought-provoking essays on the social and economic conditions that are most conducive to the formation of startup companies, How to Be Silicon Valley and Why Startups Condense in America.
Paul had sent one version of these essays to me for comment before publication, but unfortunately, I wasn't able to send in a response in time to be useful. However, Paul also sent me a followup question in email, for which our research group just happens to have some good answers. Paul wrote: "In your opinion, which US cities are the biggest startup centers after Silicon Valley and Boston? Fred Wilson is trying to convince me NYC is no 3, and I just can't believe it. Surely Austin and Seattle have more …
[Read more]
While traveling this last week I read up on
converting a Linksys WRT54G to better firmwares. I just so
happen to have one of these and while it works, it has several
limitations that I would like to do away with :)
Getting home on Saturday means that when I get up on Sunday this
is one of the first things on the list to do!
Take option one and risk my working router? No, I go to Best Buy
to pick up a second WRT54G. While I may already have one, I did
not want to chance turning my current one into a brick.
The one I picked up at Best Buy of course turns out to be a
version 5, which is a nightmare to upgrade and will soon be
returned. Linksys decided to change the hardware they use in
their routers recently. The version 5 box has less memory and
Cisco has …
A popular application server benchmark, featuring a complete open source software stack with MySQL 5.0 database, the Solaris 10 Operating System, and Sun Java Systems Application Server 9.0 Platform Edition (Project GlassFish) has shattered the competition by offering up to 8.6 times lower cost of acquisition than the comparable solution, according to the SPEC benchmark test results published at http://www.spec.org/jAppServer2004/results/jAppServer2004.html.
This article compares the relative speed of extracting the date part of a value in MySQL with LEFT() and with the DATE() function. LEFT() is faster than DATE(). To prove this, I inserted two million un-indexed sequential values into a table and selected the minimum and maximum values. Both queries are table scans, so it does read through all the records. The table below lists the time in seconds for MAX() on my computer.
At the start of this week, we suffered a corruption of our main 5.1 source code repository at MySQL. No data was lost, but I spent most of four working days on cleaning up the corruption, Monty spent one day, and many other people had to spend time on this or were stalled in their work while the problem was being resolved. Including the usual stories with fetching off-site backup tapes only to find them broken, etc.
Our source code repository is the centre that all our work in Engineering revolves around, and it just has to be stable. The confidence in the revision control software that we use suffers greatly from such an experience, and the lost confidence can never really be restored.
But there is a good lesson in this for MySQL, I think.
Like revision control software, MySQL is used by our users to store their valuable data. The database is the center around which applications revolve, and it must be …
[Read more]An update about Ubuntu: Mark Shuttleworth is coming to Moscow this week, and there will be a meeting with community. Is anyone coming? I'll be there. One reason, our CEO, Marten Mickos, is coming to INTEROP on 21st of June, and there will be no such meeting with MySQL users. So I'll go and see how to organize these things :)
The biggest current problem that I know in the MySQL servers is
the performence of information_schema. This is reported as
bug 19588:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 1829 to server version: 5.0.22-max-log
Type 'help;' or '\h' for help. Type '\c' to clear the buffer.
mysql> SELECT TABLE_SCHEMA,
-> sum((DATA_LENGTH + INDEX_LENGTH) / (1024 * 1024)) as size_mb
-> FROM information_schema.TABLES
-> GROUP BY TABLE_SCHEMA
-> HAVING size_mb > 10
-> ORDER BY size_mb DESC;
...
xxx rows in set (7 min 34.71 sec)
Even though this server hosts a lot of data - more than 7 minutes
for this query is tough.
Google offers a little Toolbar that provides additional information about
the displayed website, including the PageRank value that
indicates how "important" the website is in Google's eyes (and
that's said to be used to calculate the relevance in Google
searches).
Here are some values that I looked up:
www.mysql.com: 9/10
www.planetmysql.org: 8/10
www.google.com: 8/10
www.microsoft.com: 9/10
www.yahoo.com:
9/10
www.oracle.com: 9/10
…