If you do not know what International Women’s Day is: http://www.internationalwomensday.com/

Start planning your blog posts for Ada Lovelace day now (March 24th, http://findingada.com/ Ada Lovelace Day is an international day of blogging (videologging, podcasting, comic drawing etc.!) to draw attention to the achievements of women in technology and science.)

To that end, I would like to point out all the women currently in science and tech fields that I admire and think are doing great things. I think it would be great if everyone, male or female, made a list like this:

The women that have taught me science/tech along the way:

High School:
Mary Lou Ciavarra (Physics)
Maria Petretti (Pre-Algebra, and Academic Decathlon)
Reneé Fishman (Biology)
Lisa Acquaire …

The 181st 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 …

Cary Millsap has a concise, readable paper on performance. Anyone involved in database performance optimization should read it. Cary’s writing has heavily influenced the mk-query-digest tool for analyzing MySQL/PostgreSQL/Memcached/HTTP query performance, and I think you’ll get a lot more from mk-query-digest if you read this paper — and you should also read his book, reviewed here. It’s one of the top books on my Essential Books List.

Related posts:

1. …

I’ll be attending PgEast this year, as I’ve done for the last couple of years, and this year I’ll also be speaking. The topic is query analysis with mk-query-digest. The official description of my talk is as follows:

mk-query-digest is a powerful open-source tool for capturing, filtering, transforming, and aggregating queries, with the ability to do all sorts of other advanced tasks too. By default, it aggregates similar queries together and presents a designed-for-DBAs report with statistics about the most important queries, so you can see where to focus your optimization efforts. This talk shows you how to use mk-query-digest to analyze your Postgres server’s workload.

…

Maatkit does more than just MySQL. I’ve just committed a new version of mk-query-digest, a powerful log analysis tool, with support for Posgtres logs, in both syslog and stderr format. I’m hoping that people will give this a spin in the real world. I have lots of test cases, but that’s never enough; I’m looking for people to crunch their logs and let me know if anything breaks.

A brief tutorial:

# Get it
$ wget http://www.maatkit.org/trunk/mk-query-digest

# Run it
$ perl mk-query-digest --type pglog /path/to/log/file

# Learn about it (search for the string "pglog")
$ perldoc mk-query-digest

I’m going to close comments on this blog post so I don’t get bug reports in the comments. If you have feedback, please post it to the Maatkit mailing list, or …

You have found the 179th 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 …

Gerry Narvaja has published the 178th 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.

I explored two interesting topics today while learning more about Postgres.

Partial page writes

PostgreSQL’s partial page write protection is configured by the following setting, which defaults to “on”:

full_page_writes (boolean)

When this parameter is on, the PostgreSQL server writes the entire content of each disk page to WAL during the first modification of that page after a checkpoint… Storing the full page image guarantees that the page can be correctly restored, but at a price in increasing the amount of data that must be written to WAL. (Because WAL replay always starts from a checkpoint, it is sufficient to do this during the first change of each page after a checkpoint. Therefore, one way to reduce the cost of full-page writes is to increase the checkpoint interval parameters.)

Trying to reduce the cost of full-page writes by increasing the checkpoint interval highlights a compromise. …

Welcome, everyone, to the 177th 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 …