Pythian Group

The 181^st edition of Log Buffer has been published by Gary Myers on his Sydney Oracle Lab.

Having recently moved his blog, Gary approached the Log Buffer coordinator to volunteer for an edition because he knows that, with LB being a popular and established destination in the database blogoshphere, it would help him broadcast his new blog and welcome readers to it. You can do it too–simply send an email to the Log Buffer coordinator.

Here’s Gary’s Log Buffer #181.

Hello and welcome to Log Buffer #180. Time’s a-wastin’, so let’s go!

Oracle

There was so much Oracle stuff this week that I’ve decided to cram a little more of it into Log Buffer by providing a little less context than usual.

Jonathan Lewis shares an explication of aliases: “I was asked the following question recently: ‘Does the use of table aliases affect performance?’ To which the best answer is probably ‘Yes, though in general you probably won’t notice the difference and there are reasons more imporant [sic] than performance for using table aliases.’”

Doug Burns continues his most recent series: Statistics on Partitioned Tables – Part 2, and Statistics on Partitioned Tables – Part 3.

Charles Schultz demonstrates how VPD + bad ANYDATA practices can really bite: “The point of my blog was that using CAST can really screw up your data. Oracle Support is filing a bug on this behavior, as it looks like an overflow problem.”

Pythian’s Gleb Otochkin begins a series on Oracle GoldenGate installation.

Guy Harrison provides a thorough introduction and recommendations on memory management for Oracle databases on VMWare ESX.

Robert Vollman returns to blogging and offers his 10-point plan on improving your SQL queries.

Jared Still sheds some light on a cool but unknown RMAN feature. Read the rest of this entry . . .

You have found the 179^th edition of Log Buffer, the weekly review of database blogs. Welcome. Enjoy your stay. We begin with . . . 

SQL Server

Merrill Alrich gets going with a fresh juxtaposition–his thoughts on motorcycles and Access. “Many DBAs,” he writes, “have been called in to rescue people, or teams, or projects who have mission critical Access applications gone horribly wrong. It’s very unpleasant, especially the typical discussion we have to have with the Access afficionado . . . ”

Brent Ozar is in on this discussion too. Here he gives his top 10 reasons why access still doesn’t rock.

Brent’s blog also has an interview with Joe Sack, “ . . . public face for the SQL MCM program.”

Aaron Bertrand has a couple new items in his Bad Habits to Kick series: inconsistent table aliasing and blind SQL Server installs.

The Rambling DBA Jonathan Kehayias, advises, pay attention to maintenance cleanup job configuration, specifically with regard to backup files.

Jeremiah Peschka shows how a simple refactoring of functions in the WHERE clause can turn a performance disaster into success. Read the rest of this entry . . .

Gerry Narvaja has published the 178^th edition of Log Buffer, the weekly review of database blogs.

LB is always looking for contributors, so if you’d like to publish an edition of your own, drop a line to the Log Buffer coordinator. It’s an excellent way to put your stamp on the database blogosphere.

Here is Gerry Narvaja’s Log Buffer #178.

Welcome, everyone, to the 177^th edition of Log Buffer, the weekly review of database blogs. It was another week heavy with technical posts, so let’s waste no time, and get it all started with . . . 

PostgreSQL

David Fetter shares his recipe for adding only new rows: “Let’s say you have a table and a data set, and would like to add only those rows in your data set that aren’t already in the table. There are hard ways, but here’s an easy one.”

Simon Riggs, the Database Explorer, offers his thoughts on parallel query in Postgres: “I’m disappointed we’ve not made much progress with parallel operations and partitioning in core Postgres in last few releases. Recent Greenplum results show we have much work to do in improving things.”

David Christensen shares a PostgreSQL tip: using pg_dump to extract a single function.

Robert Gravsjö shares a screenshot of the new Sun Oracle PostgreSQL. That doesn’t even sound right, does it?

Read the rest of this entry . . .

This is the 176^th edition of Log Buffer, the weekly review of database blogs.

There were heaps of mostly technical posts this week. I think bloggers are tired of kicking around the ins-and-outs of Sun and Oracle, and wanted to talk about what really matters. So let’s start with . . . 

Oracle

Harald van Breederode shows how to setup a private DNS for your virtual cluster.

Pythian’s Alex Fatkulin discusses Oracle GoldenGate Extract Internals.

From Charles Hooper comes this investigation: Simple Query Generates Complex Execution Plan, the Mysterious 4063.88 Second Single Block Read Wait.

Coskan Gundogar was also in a deductive frame of mind. Here is his Working with statspack-part-1a-Diagnosis, featuring both a challenge and purty pictures (pastels!).

Here is Jonah H. Harris with an introduction to the NEXTGRES Gateway, a MySQL Emulator for Oracle. Jonah writes: “So, a few people have asked me what NEXTGRES Gateway is. My short answer, the ultimate database compatibility server.  . . . I’ve been working on this personal project non-stop for the last 8 months and am really excited about it.”

Read the rest of this entry . . .

Welcome to the 175^th edition of Log Buffer, the weekly review of database blogs.

Oracle

Let’s begin with remoteDBAexperts blog, and Chris Foot’s prediction of the future of database tuning and database administration. It will be, “ . . . administrators interpreting and implementing the recommendations generated by the intelligent advisors and ADDM.  . . .  I also think that Oracle will eventually become self-tuning.”

Here in the present, DBAs (Oracle and otherwise) are still Striving for Optimal Performance as Christian Antognini is. Here’s his item on join elimination, which he introduces thus: “In some specific situations the query optimizer is able to completely avoid executing a join even if a SQL statement explicitly calls for it. Two are the cases currently covered by this optimization technique, which is called join elimination.”

Jeff Hunter of the So What Co-operative was at the optimizer too, and found an interesting optimizer result, and pursued it into Interesting Optimizer Result, Part II. “If the query included the package call in the WHERE clause, the query finished in over an hour. If the package call was not in the WHERE clause, the query finished in 5 minutes (but did not return the correct results).  . . .  Confident in my fondness for inline views, I ran the query fully expecting to get the results back in a few minutes. Except the query went on, and on, and on for a full 15 minutes before I killed it.”

Kellyn Pedersen discusses what to do when PGA size is not enough. Read the rest of this entry . . .

Happy New Year to all our readers! Welcome to 2010 and the 174^th edition of Log Buffer, the weekly review of database blogs.

MySQL

The MySQL ’sphere since the holidays has been thick with posts on the matter of Oracle’s purchase of Sun, and thereby of MySQL. And in particular, there’s been a lot of talk about MySQL founder Monty Widenius’s response. I call all of this the . . . 

Monty My-Thon

On the 28^th of December, Monty framed the issue thus: Help keep the Internet free.

Singer Wang of Pythian, in reply, offers his perspective on GPL/ASL/BSD License Misconceptions and MySQL.

On Poo-tee-weet, Lukas Kahwe Smith is heard to say, Come on Monty . . .  “What on earth is Monty . . . thinking? How can you spin around 180 and expect to come of believable? How can suddenly the GPL be the wrong choice? How can suddenly OSS depend on proprietary sales?”

On the WireLust blog, Terrence Curran writes, Monty Widenius is trying to regain control of MySQL and why this is bad for OSS.

Kristian Nielsen shares some Oracle speculations, stating, “I think it is basically a matter of obtaining control over MySQL.”

Antony Curtis throws in his two cents: “The topic of today is [Monty's] ‘Save MySQL’ campaign and how I believe it is unnecessary.  . . .  In fact, I believe that it could be harmful.”

Read the rest of this entry . . .

Nicklas Westerlund has published the 173^rd edition of Log Buffer, the weekly review of database blogs, on SELECT mysqlgenie FROM lamp;.

Log Buffer will be off next week for the holidays, and back early in 2010 to begin another year of presenting the best of database blogs. Please get in touch with the Log Buffer coordinator if you’d like to publish an edition of your own.

Happy Holidays to everyone! Here is Log Buffer #173.

One week and a whole lot of snow later, it is time for the 173^rd edition of Log Buffer, the weekly review of database blogs. MySQL goes first this week.

MySQL

On the MySQL Performance Blog, Peter Zaitsev and his readers discuss the question, how many partitions can you have? In Peter’s opinion, “ . . . be careful with number of partitions you use. Creating unused partitions for future use may cost you.”

Also, Peter’s colleague Aleksandr Kuzminsky announces the release of xtrabackup-1.0, an “open source online (non-blockable) backup solution for InnoDB and XtraDB engines.”

On SELECT mysqlgenie FROM lamp; Nicklas Westerlund published the first part of a series on IO benchmarking for MySQL, showing the results of his tests with sysbench.

Nick will also be tackling next’s week’s Log Buffer.

Harrison Fisk’s MySQL Thoughts this week included this item about an Ext4 with MySQL binary logs oddity. “ . . . we were able to pin it down to ext4 and how it delays data writes for a very long time (30 minutes).”

As long as we’re in /var, here’s Eric Bergen, attempting to unwind the tangled web of pid file creation, which he started doing having discovered a pid file creation race condition in mysqld_safe.

Read the rest of this entry . . .