If you need to work with LVM in your scripts but haven’t found a good method to access details about Logical Volume Groups, here’s a simple Python script that will print the details about any volumes on your system. This could be useful for writing a partition check script for your MySQL data directory (if you’re not using a standard monitoring system like Nagios).

import sys
import os
import commands
import subprocess
import select

def lvm():
    print ""
    LVM_PATH = "/sbin"
    LVM_BIN = os.path.join(LVM_PATH, 'lvm')
    argv = list()
    argv.append(LVM_BIN)
    argv.append("lvs")
    argv.append("--nosuffix")
    argv.append("--noheadings")
    argv.append("--units")
    argv.append("b")
    argv.append("--separator")
    argv.append(";")
    argv.append("-o")
    argv.append("lv_name,vg_name,lv_size")

    process = subprocess.Popen(argv,

  [Read more...]

Following up on Matt Reid’s simple python, mysql connection and iteration, I would like to share one of my own, which is the base for mycheckpoint & openark kit scripts.

It is oriented to provide with clean access to the data: the user is not expected to handle cursors and connections. Result sets are returned as python lists and dictionaries. It is also config file aware and comes with built in command line options.

I hope it comes to use: my.py

If you’ve been looking for a simple python script to use with MySQL that you can use to expand upon for your next project, check this one out. It has error handling for the connection, error handling for the sql call, and loop iteration for the rows returned.

#!/usr/bin/python
import sys
import MySQLdb

my_host = "localhost"
my_user = "user"
my_pass = "password"
my_db = "test"

try:
    db = MySQLdb.connect(host=my_host, user=my_user, passwd=my_pass, db=my_db)
except MySQLdb.Error, e:
     print "Error %d: %s" % (e.args[0], e.args[1])
     sys.exit (1)

cursor = db.cursor()
sql = "select column1, column2 from table";
cursor.execute(sql)
results = cursor.fetchall()
for row in results:
    column1 = row[0]
    column2 = row[1]
    print "column1: %s, column2: %s"%(column1,column2)

db.close()

If you have tried Quick start guides: MySQL cluster in 10 minutes, you may have realized that it is really quick and easy.
However, it leaves some typing to be done.
Users of MySQL Sandbox have a horror of repetitive typing, and this got me thinking. "Could I integrate MySQL Sandbox and Cluster?"
The answer was: "Sure."
But then I started thinking of all the minor and major changes that I wanted to do to the Sandbox and have delayed for too long. What I need, is a radical refactoring.
And then I remembered that it has been almost two years since I learned a new




  [Read more...]

Revision 132 of mycheckpoint has been released. New and updated in this revision:

• Custom monitoring: monitoring & charting for user defined queries
• HTML reports for custom monitoring
• Process list dump upon alert notifications

Custom monitoring & charts

Custom monitoring allows the user to supply with a query, the results of which will be monitored.

That is, mycheckpoint monitors the status variables, replication status, OS metrics. But it cannot by itself monitor one’s application. Which is why a user may supply with such query as:

SELECT COUNT(*) FROM shopping_cart WHERE is_pending=1

Such a query will tell an online store how many

  [Read more...]

Just a quick notice to let everyone know that there is a new version of Kontrollkit available. There are some required bug fixes to the formerly new python backup script and some Solaris compatible changes to the various my.cnf files. You can download the new version here: http://kontrollsoft.com/software-downloads, or here: http://code.google.com/p/kontrollkit/

A special extended edition of Tech Messages for 2010-04-15 through 2010-04-24:

• The Onion Uses Django, And Why It Matters To Us
  I love Django too.
• Open Source Network Monitoring and Systems Management - Zenoss Blog: No Node Left Behind: Datacenter Barometer: BitNami Simplifies Stacks
• mysql-cacti-templates
  Offers complete templates and a method for adding your own. Highly recommended.
• Increase maximum size

  [Read more...]

I’ve recently had the pleasure of reading “Python Testing: An easy and convenient approach to testing your python projects” from Packt Publishing. It’s been a quick read but a solid set of instructions on the different methods for the subject.

The book starts out very quickly with details about the various methods that are available, the means of automation for testing, and of course the environment you’d want to be in for working on the subjects that the book covers. It then, in the second chapter, moves into the guts of testing by describing the basics of doctest via syntax and some simple examples, and then moves on to a real world example via the AVL tree. It’s all very basic

  [Read more...]

I’ve been wanting to write a backup script for a while now that does the following: reads the partition information for the directory that you are backing up into and computes the used/available/percentage-available space. Then it reads the total data size from the MySQL tables and ensures that you have enough space on disk (for [...]

Revision 118 of mycheckpoint has been released. New and updated in this revision:

• Conditional alerts
• Email notifications
• Revised HTML reports, including 24/7 reports.
• Updated documentation

With this new revision mycheckpoint turns into a monitoring solution for MySQL. One can now:

• Store measure metrics
• Query for raw, aggregated or digested metrics
• Generate charts for selected metrics
• View HTML reports for selecetd metrics
• Define alerts conditions, query for pending alerts
• Be notified via email on raised or resolved alerts.

Conditional alerts

mycheckpoint is SQL oriented. As such, it allows for

  [Read more...]

I’m pleased to announce the first release of Kontrollcomm – “The Server Command Automation Interface” is a web-based application that automates remote command execution on linux and unix based servers. There are three main areas of the application: Hosts, Templates, and Commands. The use is very simple: all of your hosts are setup in the [...]

I’m seeking input on a new openark kit utility I’ve started to implement.

The tool, oak-hook-general-log, will hook up to a MySQL (>= 5.1) server, and stream the general log into standard output. It looks like this:

bash$ python src/oak/oak-hook-general-log.py --socket=/tmp/mysql.sock --user=root
2010-03-21 10:18:42     root[root] @ localhost []       79      1       Query   SELECT COUNT(*) FROM City
2010-03-21 10:18:48     root[root] @ localhost []       79      1       Query   DELETE FROM City WHERE id=1000
2010-03-21 10:18:54     root[root] @ localhost []       79      1       Query   SHOW PROCESSLIST
2010-03-21 10:19:06     root[root] @ localhost []       79     

  [Read more...]

Most of this stuff is not PHP specific, and Python or Ruby or Java or .NET developers can use the tools in this talk.

The session on joind.in, with user comments/feedback, is at http://joind.in/talk/view/1320.

Slides are at http://talks.php.net/show/confoo10

“My name is Rasmus, I’ve been around for a long time. I’ve been doing this web stuff since 1992/1993.”

“Generally performance is not a PHP problem.” Webservers not config’d, no expire headers on images, no favicon.

Tools: Firefox/Firebug extension called YSlow (developed by yahoo) gives you a grade on your site.

  [Read more...]

After seeing quite some SQL statements over the years, something is bugging me: there is no consistent convention as for how to write an SQL query.

I’m going to leave formatting, upper/lower-case issues aside, and discuss a small part of the SQL syntax: table aliases. Looking at three different queries, I will describe what I find to be problematic table alias use.

Using the sakila database, take a look at the following queries:

Query #1

SELECT
 R.rental_date, C.customer_id, C.first_name, C.last_name
FROM
 rental R
 JOIN customer C USING (customer_id)
WHERE
 R.rental_date >= DATE('2005-10-01')
 AND C.store_id=1;

The above looks for film

  [Read more...]

Just a quick notice to let everyone know that there is a new version of Kontrollkit available. There are two new scripts included as well as some good updates to the my.cnf files. You can download the new version here: http://kontrollsoft.com/software-downloads kt-mysql-systemcheck – generates a report for point-in-time system status that is useful for troubleshooting MySQL [...]

This is a simple matter with a simple solution that might help someone save time and confusion. Emacs wasn’t coloring my comments correctly so I went ahead and had it change them to red-italic. If you are having similar issues you can drop the following into your home directory’s .emacs file. Enjoy. Keep in mind that if you are using emacs in a terminal session as opposed to the X-server gui then you will not see the italics.


(global-font-lock-mode 1)
(custom-set-variables
'(gud-gdb-command-name "gdb --annotate=1")
'(large-file-warning-threshold nil))
(custom-set-faces
'(font-lock-comment-face ((((class color) (background light)) (:foreground "red" :slant italic)))))


Looking around on Google for a webpage test script returns a lot of results. Some of them are useful, some are not. In particular, for Python, the scripts on the first page of results are minimal and lacking a useful copy and paste / ready to go script that will answer the question “is my webpage available?”. So I decided to write a quick one that will give you the return code and email you as an alert if the page does not return with a 200 code (successful). You can find the script here. Update: the webserver was trying to execute the script as a .py file so I just changed it to .txt – for it to work you will want to change the .txt extension to a .py extension after you download it.

If you are familiar with Python scripting, this script could easily be modified to post to a form so that you can

  [Read more...]

At Fosdem 2010, already two weeks ago, I had the pleasure of hearing Geert van der Kelen explain the work he has been doing on connecting MySQL (http://www.mysql.com/" target="mysql) and Python. I don't know anything about Python, but anybody that has the courage, perseverance and coding skills to create an implementation of the the MySQL wire protocol from scratch is a class-A programmer in my book. So, I encourage everyone that needs MySQL connectivity for Python programs to check out Geert's brainchild, MySQL Connector/Python.

In relation to MySQL Connector/Python, I just read

  [Read more...]

Dave Edwards has offered me to write this week's Log Buffer, and I couldn't help but jump at the opportunity. I'll dive straight into it.

Oracle

I'll start with Oracle, the dust of the Sun acquisition has settled, so maybe it's time to return our attention to the regular issues.

Lets start with Hemant Chitale's Common Error series and his Some Common Errors - 2 - NOLOGGING as a Hint explaining what to expect from NOLOGGING. Kamran Agayev offers us an insight into Hemant's personality with his Exclusive Interview with Hemant K Chitale. My favorite quote is:

Do you

  [Read more...]