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Mysqldump fails as a cron job - a work around

Here's a curiosity ... running a mysqldump as a crontab job, nothing happens on one of our servers. Now I HAVE included the full path to the executable file in my crontab line, and I have ...

Grouping rows for a summary report - MySQL and PHP

It's quite quick and easy to write a loop that goes through a mysql result set and displays the content on an HTML page (but remember security of data, size of resulting HTML page, and the need to ...

How do I query a database (MySQL)?

From my mailbox ... "What are the different ways of queries in databases? Could u pls explain each way in more detail? thanks" The term "query" means something a little bit different in the term ...

MySQL server replication

Following on from yesterday's article about MySQL tuning ... there may come a time that a single server can't cope. What should you do? Consider replicating your server. This works well if you've ...

Monitoring and Tuning your MySQL installation

How much memory does MySQL occupy? Is it efficient / does it need more memory? Can I tune it? All good questions ... and to make the most of any answers, there's something you'll need to know first ...

Images in a database? How big is a database? (MySQL)

The discussion came up yesterday as to whether images should be stored in plain files or in a database, with one of my delegates saying that he had been strongly advised against a database. That ...

Oracle take over Sun who had taken over MySQL

The newspaper tells me that Oracle is buying Sun Microsystems. Since Sun Microsystems bought MySQL about a year ago, this means that Oracle now owns MySQL. I wonder what they will do with it. I am ...

MySQL - looking for records in one table that do NOT correspond to records in another table

Q: Can you give an example where I can retrieve all the records of a table "users" where there are no corresponding records in other table "user_role" A: No (sorry - I'm too busy to set up tables of ...

MySQL - licensing issues, even with using the name

MySQL is a really good database and it's been available for a very long time under an open source license - indeed this piece of text will be stored in a MySQL database when I've added it to our web ...

Setting up a MySQL database from PHP

Yes ... training on a Sunday ;-) ... I've been setting up a MySQL database from a PHP script and testing it. A couple of bits of source to share. 1. The setup of the database: <?php ...

What a difference a MySQL Index made

If you add an index to a column in a MySQL table, you provide a very quick way of looking up a row or set of rows based on the value in a certain column, but at the expense of additional disc space ...

Summary of MySQL installation on a Linux system

The critical steps of deleting an old copy of MySQL, and installing and starting up a nice new clean one! (the numbers are my "history number" - I did a lot of ls-ing and vi-ing in between!) 1001 ...

Ruby, Perl, Linux, MySQL - some training notes

We have just come to the end of a solid 12 days of training ... and we are just getting ready for the next week, with delegates arriving this evening. There's a lot going on behind the scenes, even ...

MySQL database from Ruby - an example

Both MySQL and Ruby are huge subjects - the former being an excellent database engine and the latter a superb programming language. Yet although each individually is a huge subject, linking the two ...

Hiding a MySQL database behind a web page

"Keep the browser simple - with a single route in (http) to a server." That's the philosophy behind the web and one of the things that's made it a huge success. It means that a straightforward ...

More HowTo diagrams - MySQL, Tomcat and Java

Here are some more diagrams "off the wall" from last week - showing "howto" and "whatis" information for Tomcat, Java and MySQL Some Tomcat and Java Fundamentals On the right of the board ... the ...

Finding words and work boundaries (MySQL, Perl, PHP)

If you're searching for the word "mile", you probably don't want the page that tells you that Sally Smiled at Harry. But you may want to find a Milestone, even if it is within quotes. Regular ...

Apache httpd, MySQL, PHP - installation procedure

If you're installing LAMP (Linux, Apache, MySQL, PHP), what do you do and in which order? Here's a summary of the procedure we followed on todays Apache httpd deployment course - in this case ...

addslashes v mysql_real_escape_string in PHP

One of the most popular pages on our website is the one that shows you how to upload an image and store it in a database. And the associated demonstration showing you how to view images via a PHP ...

Making PHP and MySQL training relevant to the course delegates

If I'm training on MySQL or PHP, I'll often come up with an example in front of the class - it's much more effective training to see HOW an answer is reached than to simply be presented with a ...

Database design for a shopping application (MySQL)

Here's a "proof of concept" demo from yesterday's MySQL session - a plan for the various tables that might be involved, and a few sample columns to see how "the whole" would work together. On one ...

Joining MySQL tables revisited - finding nonmatching records, etc

A join lets me connect two tables one to the right of the other. Here's an example. First table - estate agents: mysql> select agent,town,aid from agents; ...

Uploading to a MySQL database through PHP - examples and common questions

One of the most popular pages on the technical part of our web site relates to the uploading of images to a server from a local disc file via a browser, then storing those images on a database, and ...

Downloading data for use in Excel (from PHP / MySQL)

Requirement: To allow a visitor to your web site to click on a link that downloads data from the server into a Microsoft Excel spreadhseet. Solutions - I'm going to offer you two: a) To send the ...

Ongoing Image Copyright Issues, PHP and MySQL solutions

I actually want to encourage people to use my images ... but to do so with permission, which usually means something as simple as a link back you our page which works out for everyone's benefit. A ...

Perl, PHP, Python, Tcl, Linux, MySQL, Ruby courses ...

What's this list got in common (apart from all being countries?) BelgiumEnglandFinlandFranceGermanyGuernseyIrelandNetherlandsNorwaySaudi ArabiaScotlandSloveniaSwedenUSAWales They're all countries ...

Connecting to MySQL 5 from PHP on Mac OSX Leopard

What is the difference between "localhost" and "127.0.0.1"? Everything, it seems, when you're trying to connect MySQL (and I have version 5.0.37 Community at the moment) running on Mac OSX - the ...

MySQL - table design and initial testing example

"Examples are either simple as to be trivial, or too complex to understand" said a delegate - so this afternoon I accepted his challenge to come up with some thing in between. And the example is for ...

Using PHP to upload images / Store on MySQL database - security questions

Yesterday, the page on our website that shows you how to upload an image from a browser in a PHP script, store the image in a database, and later on retreive and redisplay the image, was visited 250 ...

Using a MySQL database to control mod_rewrite via PHP

Question: How can I set up Apache httpd / mod_proxy to use a program rather that a list of URL patterns to control my rewrites? Specify a rewrite map type prg in your httpd.conf or .htaccess file. ...

MySQL joins revisited

Sameer writes: "Nobody can clear JOINS as this manual has done. It is SUPERB.. Thanks. It helped me a lot to understand. I will appreciate if you can make much clear to the INNER AND SELF JOINS." in ...

Outputting numbers as words - MySQL with Perl or PHP

Oracle's in_char function lets you convert numbers into a text string, but it's an unusual facility to have as as built-in; there's no such facility (as far as I know) in MySQL but you can get around ...

MySQL - the order of clauses and the order of actions

You specify your select command in the following order: 1. The columns you want to choose (SELECT) 2. Where you want to send the results (INTO) 3. The tables that contain the data (FROM) 4. How you ...

MySQL - Password security (authentication protocol)

Ever had this message? bash> mysql -h www.weekendinwiltshire.co.uk -u weekend -p Enter password: ****** Client does not support authentication protocol requested by server; consider upgrading MySQL ...

mysqldump and mysqlrestore

It is vital that you back up your data ... and if you hold your data in a MySQL database, then the mysqldump utility will do the job admirably for you. It is equally vital that you can restore the ...

Apache httpd , browser, MySQL and MySQL client downloads

If you download a copy of the Apache httpd web server, does it come bundled with a browser as well? No - it doesn't. Although you'll access your web server through a browser most of the time (or ...

.pdf files - upload via PHP, store in MySQL, retrieve

There's a common requirement to manage binary data - upload from a user, store, bring back in a web page. And where you have a substantial number of pieces of data - a lot of .pdf documents, .jpg or ...

Display an image from a MySQL database in a web page via PHP

There's lots of clever scripts around to tell you how to get images in and out of databases, but nothing simple to show you the principles of including such an image via (say) PHP in a web page. So ...

The LAMP Cookbook - Linux, Apache, MySQL, PHP / Perl

It all started on Friday as we came back from the pub. I was describing how we've been, twice, on Neil Bauman's Geek Cruises but never been asked to talk or lecture, even in a "lightning session" on ...

Browser -> httpd -> Tomcat -> MySQL. Restarting.

I've just completed a course covering the installation and configuration of Apache httpd, Apache Tomcat and MySQL. Complete with a demonstration that has the newly installed systems visited from ...