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Chitu Okoli chitu.okoli.org

Computers and the Internet

Computers, networks, the Internet, telecommunications and other things powered by 0s and 1s.

Display advanced Unicode in Oracle SQL Developer

Posted by on Jan 25, 2016 in Computers and the Internet | 2 comments

It can be tricky sometimes to display Unicode characters in Oracle SQL Developer. For most Unicode characters, the UNISTR function will do the trick: UNISTR(‘\25CF’) will display ●, UNISTR(‘\2192’)will display → and UNISTR(‘\2020’)will display †. To see the display, you can execute select UNISTR(‘\2020’) from dual; to display †. However, some Unicode characters in higher code blocks can’t be expressed in four hexadecimal characters. For example, the code for 🍁 (a maple leaf) is...

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Create test data for a database with foreign keys

Posted by on Dec 1, 2015 in Computers and the Internet | Comments Off on Create test data for a database with foreign keys

There are various free data generators to create test or dummy data for a database, but generally speaking, they don’t handle foreign keys between tables very well. This video shows how to create random data from a free test data site, manipulate the tables in Excel to maintain foreign keys and other advanced referential integrity logic, and then convert the data to SQL insert statements.

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Sending PHP mail from localhost

Posted by on Jul 26, 2013 in Computers and the Internet | 3 comments

Here I provide instructions on sending PHP mail from localhost, that is, from a local development machine. I only tested this on Windows, but it should work with any localhost setting. In trying to test PHP code on Windows development machine using a WAMP stack like AMPPS or XAMPP, you might want to send mail from PHP. This should be pretty easy to do from code hosted on a hosting provider (for example, my host 1&1 provides simple instructions), but it wasn’t so easy for me from a local WAMP stack. Fortunately, I came across a blog...

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Yahoo e-mail seems to be easily hacked

Posted by on Jul 16, 2013 in Computers and the Internet | Comments Off on Yahoo e-mail seems to be easily hacked

Yahoo e-mail accounts seem to be hacked more easily than any other e-mail service. For those who have Yahoo e-mail accounts, I recommend you switch to Gmail.

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How to cite code borrowed from other sources

Posted by on Jul 13, 2013 in Computers and the Internet | Comments Off on How to cite code borrowed from other sources

To cite code borrowed from other sources, the main concern in avoiding plagiarism is that you acknowledge that it is not your own work. Most fundamentally, you need to add a comment in your code that makes two things clear: The code you are using is not your own original work; and what is the source of the code you borrowed, usually indicated with a URL. For example, suppose I am writing a JavaScript program. I need a function that sorts an HTML table by columns, and I find the following code on the site http://example.com/sort.js: function...

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Web development resources and links

Posted by on Jul 9, 2013 in Computers and the Internet | 2 comments

This page compiles various useful web development resources and links that I have used or come across and that I recommend. I add to it incrementally. Please suggest other useful resources in the comments below.

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Windows 7 screen shut-off

Posted by on Jun 3, 2013 in Computers and the Internet | Comments Off on Windows 7 screen shut-off

On my brand new work computer running Windows 7, there was a very irritating “feature”. Every few minutes, the screen would blank out. When I shook the mouse to continue, I would have to log back in to my account (CTRL-ALT-DEL and password) each time. I played around with lots of power settings to no avail. Here’s what finally worked: the problem was that the screen saver was setting things off. It was very non-intuitive in my case since the screen saver was set to “None”, yet when I finally looked at the screen...

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Reverting Joomla articles

Posted by on Jul 9, 2012 in Computers and the Internet | Comments Off on Reverting Joomla articles

I had a scare today. Running on Joomla 1.5.23 and logged in, I clicked the icon for adding a new article at the end of a Category List Layout listing. Pressing this "new article" icon does not show the new article creation page–rather it sends the user to edit the home page! I was  in a hurry and not being careful, so I deleted the information there and then entered information for the new article. Soon after I saved it, I realized that I had just replaced my home page with a new article! After a few minutes of...

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Lenovo ThinkPad T510: Windows 7

Posted by on Aug 29, 2010 in Computers and the Internet | Comments Off on Lenovo ThinkPad T510: Windows 7

Lenovo ThinkPad T510: Windows 7

My ThinkPad T510 came with Windows 7 64-bit preinstalled. For my previous ThinkPad T43, I had completely deleted Windows XP, since I had no use for it. However, Windows 7 is the best Windows ever, so I've kept it for dual-booting every now and then. However, since I have a pretty good setup to run Windows programs under Linux, I don't run Windows 7 much. Here I describe some of the key application and system software I've installed on Windows 7 beyond the default programs installed on a ThinkPad.

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Lenovo ThinkPad T510: Ubuntu

Posted by on Aug 29, 2010 in Computers and the Internet | Comments Off on Lenovo ThinkPad T510: Ubuntu

Lenovo ThinkPad T510: Ubuntu

Since Fall 2006, I've used Ubuntu, the most popular version (distribution or distro) of Linux. I started with Ubuntu (the Gnome version), switched soon after to Kubuntu (the KDE version) because its GUI seemed more Windows-like to me, and then eventually returned to Ubuntu because of its superior stability over Kubuntu. My reason for switching from Windows XP to Ubuntu was that I was sick and tired of my computers slowing down after a few months of Windows use, and even for my desktop from disappearing to the point that I would have to reinstall Windows and all my programs. In Fall 2006 I had such a total Windows desktop failure that I had to reinstall Windows to fix it. I decided that I might as well switch to Linux, since a new operating system (OS) would be about as painful as having to reinstall my entire Windows system. Actually, it was much more painful, since Linux is far from perfect, but whenever I considered the alternative (returning to Linux), I realized that I can never go back. When Windows Vista came out, I certainly had no regrets. Linux is just far superior to Windows for power users like me. However, Windows 7 is sufficiently good that with my ThinkPad T510, I now double-boot Ubuntu and Windows 7, though Ubuntu remains my primary OS.

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