Posts Tagged ‘SQL Server’

Log Buffer #113: A Carnival of the Vanities for DBAs

By David Edwards September 5th, 2008 at 11:49 am
Posted in Log BufferMySQLNon-Tech ArticlesOraclePostgreSQLSQL Server
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This is the 113th edition of Log Buffer, the weekly review of database blogs.

Sheeri Cabral gets things going this week with her coverage of this rumour: Monty Widenius Leaves Sun/MySQL. If it turns out to be true, that seems like bad–or at least sad–news for MySQL, but Sheeri’s take is mostly an optimistic one.

MySQL’s Kaj Arno responds to the rumours on Monty resigning: “First, it’s a rumour.  . . .  Second, Monty’s resignation has been a possible outcome already since years before the Sun acquisition.  . . .  I can neither confirm nor deny the rumour.”

On CNET’s The Open Road, Matt Asay says. “Monty has done the right thing with his dissent. He has taken it outside the company, as Arjen Lentz, MySQL’s twenty-fifth employee, did before him. Arjen continues to be both a promoter and critic of MySQL, but is able to do so publicly without the constraints of an employee agreement. I assume Monty will do the same, and rightly so.” That’s not all the response out there, and there will certainly be still more as this develops.

In non-Monty blogs, Brook Johnson of Database Science asks, can a timestamp be slower than a datetime? (more…)

Sheeri’s Sordid Past

By Sheeri Cabral September 5th, 2008 at 12:22 am
Posted in MySQLNon-Tech ArticlesNot on Homepage
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I confess — I have not always been an exclusive MySQL user. I have fooled around with other DBMSs. I was young, inexperienced, and I needed the money, I swear!

This comes about because I was doing some electronic de-crufting….From a file last modified on 10:50 am on 2005-06-30:

> more addcatalog.sh
#!/bin/sh

 db2 catalog tcpip node $1 remote $2 server 50000
 db2 terminate
 db2 catalog database sample as $2 at node $1
 db2 terminate

# [db2inst1@midgard db2inst1]$ db2sql92 -a db2inst3/password -d coworkername

And from the same time-frame there’s also:

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Log Buffer #112: A Carnival of the Vanities for DBAs

By David Edwards August 29th, 2008 at 11:48 am
Posted in Log BufferMySQLNon-Tech ArticlesOraclePostgreSQLSQL Server
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Welcome to the 112th edition of Log Buffer, the weekly review of database blogs.

First, thanks to last issue’s contributors–Joe Izenman, Dan Norris, and Jason Massie–for snatching victory from the jaws of defeat and making LB#111 a worthwhile read. That’s what it’s all about!

Oracle’s up first, starting with our old friend Doug Burns and his Time Matters series, in which he holds up to the light the concept of DB Time: “. . . [the] total time spent by user processes either actively working or actively waiting in a database call.” He continues, “There’s a lot more I could say about DB Time. Like all of the best performance concepts or methods (e.g. YAPP, Method-R) it can seem so obvious as to not be worth saying, but contains an enormous amount of common sense and technical rigour.”

Arup Nanda writes about the time he spent Diagnosing Library Cache Latch Contention. About half an hour, as it happened, but he’s a real pro, and his analysis just goes to show. To quote, Nuno Souto–who makes the best blog endorsements– “Damn useful stuff . . .  bookmarked.”

Tanel Poder has another script for you to fall in love with, which makes its debut in flexible sampling of any V$ or X$ view with sample.sql. It is, writes Tanel, “ . . . a simple but powerful sqlplus script for ad-hoc sampling of any V$ view.”

Kenneth Downs, the Database Programmer, offers Advanced Algorithm: Sequencing Dependencies, a smart look at satisfying dependencies in databases. What does that mean? Well for example, Kenneth writes, “All popular Linux distributions have a package installation system in which each package lists its required dependencies. If you want to install a large number of packages in one shot, producing a tangled bunch of related dependencies, today’s algorithm can be used to work them all out.”

That’s the kind of task for which we humans use tools like mind maps. Jason Arneil shares his ASM Mind Map.

Laurent Schneider went off-road and came back something not on the map at all: the difference between rollbac and rollback.

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Log Buffer #111: A Carnival of the Vanities for DBAs

By David Edwards August 22nd, 2008 at 11:13 am
Posted in Log BufferMySQLNon-Tech ArticlesOraclePostgreSQLSQL Server
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Crisis has struck! This week’s Log Buffer editor had to beg off at the eleventh hour when his time vanished. It happens. But, in every crisis, an opportunity (well . . .  maybe, maybe not). The opportunity — an open discussion of this week’s best database blog articles. Readers in control.

Log Buffer is always looking for editors, so if you’d like to step forward and publish one on your own blog, read the Log Buffer guidelines and send me an email.

I’m going to go through my bookmarks and add my own presently. I hope to hear from you!

Log Buffer #110: A Carnival of the Vanities for DBAs

By David Edwards August 15th, 2008 at 11:46 am
Posted in Log BufferMySQLOraclePostgreSQLSQL Server
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Welcome to the 110th edition of Log Buffer, the weekly review of database blogs.

From the MySQL side, Jeremy Zawodny gets things going this week. He writes about his doubts over the long-term performance of InnoDB, specifically the cost of multiversion concurrency control, particularly in a master-slave arrangment or a DW. Jeremy comments, “[The] disk bloat, fragmentation, and ongoing degradation in performance may be an argument for having some slaves that keep the same data in MyISAM tables.” His readers, however, point out some diagnostics and tools to remedy this concern.

Not that MyISAM is without foibles. Case in point, on the MySQL Performance Blog, Peter Zaitsev says, Beware of MyISAM Key Cache mutex contention. “. . . inserting in parallel into different tables when indexes fit in memory results in very bad contention causing hundreds of thousands of context switches per second with far less work done than one would hope.” Happily, as Peter reports, multiple key caches mitigates.

Peter also surveys the choices for picking a datatype for STATUS fields — “. . . ’new’, ‘confirmed’, ‘in production’, ’shipped’ status of job, message etc. People use variety of ways to handle them often without giving enough thought to the choice which can cause problems later.” VARCHAR(N), ENUM, TINYINT — which is right for the job?

Here on the Pythian Group Blog, Nicklas Westerlund demonstrates adding a unique constraint on a table with duplicate data.

Also here at home, Sheeri Cabral’s item on why you want to switch to MySQL 5.1. She argues that additions such as online ALTER TABLE, online table-based logging, and INFORMATION_SCHEMA.PROCESSLIST are compelling features worth an upgrade.

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Log Buffer #109: A Carnival of the Vanities for DBAs

By David Edwards August 8th, 2008 at 12:00 pm
Posted in Log BufferMySQLNon-Tech ArticlesOraclePostgreSQLSQL Server
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It’s time again for another edition of the weekly review of database blogs, Log Buffer. Since it was a big week for SQL Server, let’s start there, shall we?

The big news — SQL Server 2008 is released, as reported by SqlServer-qa.net, in seven different versions. Aaron Bertrand introduces a new kid on the block: SQL Server 2008 Web Edition — “. . . designed for highly available Internet facing web serving environments for the next generation Windows Server,” according to MS. (I’ve heard it rains quite a lot in Seattle. I guess it also Drizzles, too.) Says Aaron, “Basically, it has higher scalability than Express or Workgroup Editions : it supports up to 4 CPUs, no artificial limit on RAM, and unlimited database size.”

(Before you crack open your server case, Tara Kizer on Ramblings of a DBA has some advice on how to get physical CPU count on a server.)

The SQL Server Express Express blog helpfully offers a table outlining the differences in the features of the differences between SQL Server 2008 Express editions.

A couple little issues with the release have already emerged. Here’s Euan Garden on SQL Server 2008 Installation Confusion, VS 2008 Sp1 and NetFx 3.5 Sp1: “SQL Server 2008 has dependencies on (and includes) VS 2008 SP1 and its components (BIDS is just VS 2008, SSMS uses components), plus NetFx 3.5sp1. SQL includes the RTM versions of both of these, HOWEVER they are not broadly released yet. There is a check in SQL Server Setup that if you have an old version (Beta, RC, whatever) it will bounce the install and ask you to upgrade to the RTM bits…which of course are not yet available independent of SQL.” Click through for the KB and some other help. Denis Gobo and his readers have some more to say about this.

In all this change, you may lose sight of an important fact or two, and you may ask yourself, how did I get here . . . what version of SQL Server am I running? A couple resources are shared by Kevin Kline.

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Log Buffer #108: A Carnival of the Vanities for DBAs

By David Edwards August 1st, 2008 at 11:54 am
Posted in Log BufferMySQLOraclePostgreSQLSQL Server
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Welcome to the 108th edition of Log Buffer, the weekly review of database blogs.

With almost no ado at all, let’s begin with the bad news–from StatisticsIO and Jason Massie: The Death of the DBA. And who is the perpetrator of this crime? The Cloud! It sounds like something from a John Carpenter movie, doesn’t it?

Let’s see what Jason is thinking. “I’d like to retire a SQL Server DBA with 40 years experience but I don’t think that will happen. The cloud is coming and it is bad news administrators, database or otherwise.  . . . Let’s make some assumptions. The features get there. The availability gets there. The platform basically matures . . . Now put yourself in the IT decision maker’s shoes. No upfront capital expenses, no managing backups, and no patch management.  . . . If they can remove their focus from managing and deploying IT, they sell and service more widgets.”

Scary stuff, right? Well, the commenters don’t entirely agree. I think it will be at least a factor, but I wonder how many managers will look at “The Cloud” and feel uncomfortable about privacy, data retention, and the like. (For myself, I couldn’t even endorse the idea of putting this blog’s comments into “The Cloud”.) What do you think?

Elsewhere on StatisticsIO, Jason has a note about MSDN’s SQL Heroes contest, whose aim is to, “. . . create a community project in CodePlex based on SQL Server 2008.” Jason also links to a list of CodePlex’s active SQL Server projects.

Turning to matters technical, Jeff’s SQL Server Blog offers a lesson on converting input explicitly at your client: don’t rely on the database to “figure it out”. Jeff takes the example of formatting dates, and show both the right and the wrong way, writing, “I’ve said it over and over and I’ll say it again: The concept of formatting dates should never be something that your database code should ever worry about.”

On the Less Than Dot blog, SQLDenis observes that converting columns to date from datetime does not result in a scan in SQL Server 2008. What you get instead is a seek, as he demonstrates.

Indexing Foreign Keys - should SQL Server do that automatically? So asks Greg Low on the The Bit Bucket. “By adding indexes on the foreign keys on three tables,” he writes, “we saw a reduction of 87% in total I/O load.  . . . it really struck me that having SQL Server do this by default would avoid a lot of apparent performance problems.  . . .  Should SQL Server simply do this by default when you declare a foreign key reference?”

Kent Tegels of Enjoy Another Sandwich — riddle me this, riddle me that! “When is a bug not a bug?” I give up, Kent. When is a bug not a bug? (more…)

Log Buffer #107: A Carnival of the Vanities for DBAs

By Keith Murphy July 25th, 2008 at 11:05 am
Posted in Log BufferMySQLNon-Tech ArticlesOraclePostgreSQLSQL Server
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Welcome to the 107th edition of the Log Buffer. My name is Keith Murphy and I am a MySQL database administrator for the Pythian Group. In addition, I am the editor of MySQL Magazine. This is my second go for the Log Buffer, so I must be doing something right!

This week for the open source world brings OSCON in Portland Oregon. There are plenty of MySQL people present and there have been more posting this week from these realms than normal. Also, Lewis Cunningham, among others, posted news that EnterpriseDB released the results of their open source survey at OSCON. The 451 CAOS Theory published their thoughts on the survey.

Of interest to all DBAs is John Duncan’s post about what is called the “five minute rule”. This was introduced in 1987 by Jim Grey. And finally, before we dive into the specific server news, here is a post on Facebook’s project to build a distributed database similar to Google’s BigTable.

MySQL News:

Friday saw the release of the summer issue of MySQL Magazine. The highlights of the issue include the first annual MySQL Usage Survey. The magazine is available here. Peter, over at Percona, shows some initial benchmarks for the latest version (0.9.8) of Sphinx. If you aren’t familier with Sphinx, it is a full text search engine that easily integrates with MySQL.

Probably the biggest news this week was the announcement by Brian Aker of “Drizzle”. It is what amounts to a slimmed down version of MySQL server. These comments are from his initial post “Stored Procedures, Views, Triggers, Query Cache, and Prepared Statements are gone for now.” Interesting. My co-worker, Sheeri K. Cabral, posted a video of Brian Aker talking about the Drizzle project at this week’s OSCON. Monty Widenius writes a good summary how Drizzle can/might integrate with the MySQL “ecosphere” at large. It was very good to hear Monty say that Sun management is encouraging this project. There has been some other interesting posts about this as well including Arjen’s thoughts, and Paul McCullagh’s. Brian Moon gives a very thoughtful view on how Drizzle could potentially fit in at dealnews. While I could probably fill up the entire Log Buffer with links to post about Drizzle, I better leave it at that.

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Log Buffer #106: A Carnival of the Vanities for DBAs

By Don Seiler July 18th, 2008 at 10:14 am
Posted in Group Blog PostsLog BufferMySQLOraclePostgreSQLSQL Server
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Greetings from Wisconsin! Welcome to the 106th edition of the Log Buffer. Mr. Edwards is on a brief holiday and kindly asked me to fill in for him. So join me as we take a tour of some of this week’s database blogging activity.

I’d like to start by sharing the story of MySQL engineer Andrii Nikitin’s young son, Ivan. The short story is that Ivan is in need of a bone marrow transplant and that would also require travelling outside of their native Ukraine for the procedure. The family is asking for donations to cover the cost of the operation and trip, so please consider donating via the previous link.

Now, moving on to the database topics, we begin with my own area of (relative) expertise, Oracle. The big news this week is the July 2008 CPU, or Critical Patch Update, which Oracle releases quarterly. The Integrity blog has a nice summary of what’s included in this latest patchset. I’m sure plenty of you will be heading to Oracle OpenWorld 2008 as well, and OTN’s Justin Kestelyn announced a community preview page with some sneak peeks of what to expect (spoiler: beer!).

In a quick round-up of Oracle 11g topics, Amit Bansal at AskDBA.org has a nice guide for installing Oracle 11g on Solaris 10. Meanwhile, Oracle performance guru (and fellow Wisconsin native) Greg Rahn makes a great case for using incremental global statistics on partitioned tables. I see that Tim Hall has taken a break from reviewing summer blockbusters to write up a nice article on AWR baseline enhancements in Oracle 11gR1, and Alex Nuijten at AMIS has a nice presentation on using Oracle 11g’s virtual columns to clean up your data model.
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Log Buffer #105, a Carnival of the Vanities for DBAs

By Sheeri Cabral July 11th, 2008 at 11:03 am
Posted in Group Blog PostsLog BufferMySQLOraclePostgreSQLSQL Server
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This week, database blogs seemed to talk about conforming to stereotypes as well as breaking them.

Fulfilling the stereotype of Microsoft software being unsecure, Microsoft released a very important SQL Server update that Aaron Bertrand notes patches “four elevation of privilege vulnerabilities.” That’s right, not one, not two, but four!!! At least there is a patch now……go forth and patch! Usually it is MySQL that throws ambiguous warnings or errors which are not an accurate representation of the actual error, but Bertrand also notes that there is A Little Management Studio Oops.

Contrary to stereotype, Microsoft is giving away content with NO DRM! Kalen Delaney asks, Did You Know the History of SQL Server? and shares a link to a chapter from a book on SQL Server 2000 in the Inside SQL Server series.

The PSS SQL Escalation Services team has fought many times about SQL Server I/O Bottleneck, I don’t have one, YES YOU DO! The team gives some reminders about how to interpet averages properly.

Allen White asks about Tools for the Reluctant DBA — that is, a programmer or administrator so good at databases that they were promoted to DBA, but may not actually want the job. Check out the comments and add your own.

Tibor Karaszi shares his stored procedure to find physical index details. Now you can use one stored procedure does what a stored procedure plus 3-4 tables ordinarily does.

But wait! There are some more updates!

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