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Articles tagged with: MySQL

Remove Duplicate Posts in WordPress

December 5, 2009 – 10:28 pm | 11 Comments
Remove Duplicate Posts in WordPress

Below is the SQL script that will attempt to identify and remove duplicate posts in your WordPress database. This script can be useful for autoblogging. If you use plugins like WP-o-Matic to pull full-text RSS …

Duplicating WordPress Installation

June 25, 2009 – 2:51 pm | 5 Comments
Duplicating WordPress Installation

Whenever you upgrade your WordPress installation or do development work, it is always a good idea to be working on a copy of your main site and not on the real thing. Copying WordPress installation …

Restart Apache, MySQL When Low on Memory

June 25, 2009 – 4:27 am | 17 Comments
Restart Apache, MySQL When Low on Memory

Heavy traffic, hungry SQL queries, leaky applications will eventually leave your server low on memory. Apache will go on a hunt for swap space and MySQL will start freezing in thoughtful contemplation. Your hard drives …

MySQL Global Search and Replace Script

June 25, 2009 – 3:53 am | 15 Comments
MySQL Global Search and Replace Script

A day will eventually come when your need to find and replace a string of text in your database. You don’t know which row, or which column, or which table. Heck, you may not even …

Passing MySQL Commands from Shell Script

June 25, 2009 – 3:30 am | 5 Comments
Passing MySQL Commands from Shell Script

Running MySQL commands from a shell script is a relatively simple task that has a lot of people baffled. Some say its too complicated and suggest using PHP or Perl, others claim doing so is …

WordPress Quick Upgrade for Linux

June 13, 2008 – 6:22 pm | 4 Comments
WordPress Quick Upgrade for Linux

Never ever upgrade WordPress to the latest version as soon as it comes out, unless you want to be the guinea pig dealing with the new bugs and incompatible plugins. Even if the new version …

Improving WordPress Performance

May 4, 2008 – 12:39 pm | 8 Comments
Improving WordPress Performance

WordPress is a great blogging engine and decent CMS. Unfortunately, most available WordPress themes- even those claiming to be “minimalist” – are bloated and slow to load. Heavy CSS stylesheets, multiple Java scripts, numerous graphics …

Convert MySQL table to CSV file

March 27, 2008 – 4:41 pm | 6 Comments
Convert MySQL table to CSV file

CSV is a field-separated format that can be easily imported into a spreadsheet application. Usually the separator field is a comma. However, sometimes it is easier to select a more unusual character (like “@” for …

MySQL query cache

August 17, 2007 – 11:15 am | 4 Comments
MySQL query cache

Query cache can significantly speed up database operations for identical search queries. This is particularly useful for Web server applications, where multiple requests for the same data are a regular occurrence.
To enable query caching on …

MySQL LOAD DATA Syntax

January 2, 2007 – 8:33 am | 3 Comments
MySQL LOAD DATA Syntax

Using LOAD DATA LOCAL INFILE is a much faster way to insert lots of data into a table than using INSERT. The only preliminary step is to format the input file with unique field separators.
In …

Creating table indexes in MySQL

November 21, 2006 – 6:32 pm | 9 Comments
Creating table indexes in MySQL

Creating an index for specific columns in a database table can greatly speed up search operations. This is important for any database query that use WHERE in the SQL string. Below is a practical example …

The correct MySQL GRANT syntax

September 21, 2006 – 12:18 pm | 4 Comments
The correct MySQL GRANT syntax

It is surprising how many people run into problems trying to use the GRANT command: everything from not being able to access a database table to losing admin access to MySQL altogether. There’s a bunch …

Simple network monitoring with ping

April 11, 2006 – 10:12 am | 3 Comments
Simple network monitoring with ping

In the Spring of 2005 Comcast experienced a major DNS outage. Since then many Comcast users have switched to DNS servers that belong to Verizon and other ISPs. Comcast started taking a lot of flak …

Solaris One-Liners

March 21, 2006 – 12:41 pm | 2 Comments
Solaris One-Liners

Useful Solaris commands for system administrators

Generating complex SQL queries with shell scripts

February 21, 2006 – 9:08 am | 4 Comments
Generating complex SQL queries with shell scripts

It is sometimes necessary to use complex select and insert queries with dozens of variables. Writing such queries by hand is a tedious process and the chance of making a mistake is high. A few …

Find and Replace in MySQL

December 28, 2005 – 11:34 am | One Comment
Find and Replace in MySQL

A simple one-line command to perform find and replace operations in MySQL:

KDE 3.2 Desktop

December 26, 2005 – 7:22 pm |
KDE 3.2 Desktop

Some screenshots of KDE 3.2 running under SuSE 9.2 on an AMD 64 machine with CrossOver Windows emulator and Microsoft Office XP installed.

A general view of the KDE desktop with one of the standard backgrounds.

Here’s …

Exporting spreadsheet data to MySQL

December 9, 2005 – 2:10 am | 2 Comments
Exporting spreadsheet data to MySQL

The following is a process for migrating spreadsheet data to MySQL database using a Shell script in a Unix environment. To follow this tutorial you must already know how to create MySQL schemas and tables. …

Install PHP, Mysql, Apache2 on Solaris 9

November 21, 2005 – 11:05 am | 2 Comments
Install PHP, Mysql, Apache2 on Solaris 9

A sample procedure for installing PHP, MySQL and Apache2 on Solaris 9.

Apache MySQL PHP Solaris 8 Installation

November 21, 2005 – 11:03 am | 7 Comments
Apache MySQL PHP Solaris 8 Installation

A sample procedure for installing PHP, MySQL and Apache2 on Solaris 8.

Using GNUPlot to chart MySQL data

November 20, 2005 – 12:17 pm | 8 Comments
Using GNUPlot to chart MySQL data

The following Korn shell function connects to a MySQL database and extracts specified data, which is then plotted as a function of time using GNUPlot.  Using correct syntax is critical. Note the use of single- …

Database operations with SQL and Korn shell

November 20, 2005 – 11:46 am | 3 Comments
Database operations with SQL and Korn shell

The following Korn shell function will read the a directory containing CSV data files named server_sysstat.20051119.csv with format: