TOPIC: MYSQL
Moving from Ubuntu 10.10 to Linux Mint 10
23rd April 2011
With a long Easter weekend available to me and with thoughts of forthcoming changes in the world of Ubuntu, I got to wonder about the merits of moving my main home PC to Linux Mint instead. Though there is a rolling variant based on Debian, I went for the more usual one based on Ubuntu that uses GNOME. For the record, Linux Mint isn't just about the GNOME desktop, but you also can have it with Xfce, LXDE and KDE desktops as well. While I have been known to use Lubuntu and like its LXDE implementation, I stuck with the option with which I have most experience.
Once I selected the right disk for the bootloader, the main installation of Mint went smoothly. By default, Ubuntu seems to take care of this, while Mint leaves it to you. When you have your operating system files on sdc, installation on the default of sda isn't going to produce a booting system. Instead, I ended up with GRUB errors and, while I suppose that I could have resolved these, the lazier option of repeating the installation with the right bootloader location was the one that I chose. It produced the result that I wanted: a working and loading operating system.
However, there was not something not right about the way that the windows were displayed on the desktop, with title bars and window management not working as they should. Creating a new account showed that it was the settings that were carried over from Ubuntu in my home area that were the cause. Again, I opted for a less strenuous option and moved things from the old account to the new one. One outcome of that decision was that there was a lot of use of the chown command to get file and folder permissions set for the new account. To make this all happen, the new account needed to be made into an Administrator just like its predecessor; by default, more restrictive desktop accounts are created using the Users and Groups application from the Administration submenu. Once I was happy that the migration was complete, I backed up any remaining files from the old user folder and removed it from the system. Some of the old configuration files were to find a new life with Linux Mint.
In the middle of the above, I also got to customise my desktop to get the feel that is amenable. For example, I do like a panel at the top and another at the bottom. By default, Linux Mint only comes with the latter. The main menu was moved to the top because I have become used to having there, and switchers for windows and desktops were added at the bottom. They were only a few from what has turned out not to be a short list of things that I fancied having: clock, bin, clearance of desktop, application launchers, clock, broken application killer, user switcher, off button for PC, run command and notification area. It all was gentle tinkering, but still is the sort of thing that you wouldn't want to have to do over and over again. Let's hope that is the case for Linux Mint upgrades in the future. That the configuration files for all of these are stored in the home area hopefully should make life easier, especially when an in-situ upgrade like that for Ubuntu isn't recommended by the Mint team.
With the desktop arranged to my liking, the longer job of adding to the collection of software on there, while pruning a few unwanted items too, was next. Having had Apache, PHP and MySQL on the system before I popped in that Linux Format magazine cover disk for the installation, I wanted to restore them. To get the off-line websites back, I had made copies of the old Apache settings that simply were copied over the defaults in /etc/apache (in fact, I simply overwrote the apache directory in /etc, but the effect was the same). Using MySQL Administrator enabled the taking of a backup of the old database too. In the interests of spring-cleaning, I only migrated a few of the old databases from the old system to the new one. In fact, there was an element of such tidying in my mind when I decided to change Linux distribution in the first place; Ubuntu hadn't been installed from afresh onto the system for a while anyway and some undesirable messages were appearing at update time though they were far from being critical errors.
The web server reinstatement was only part of the software configuration that I was doing, and there was a lot of use of apt-get while this was in progress. A rather diverse selection was added: Emacs, NEdit, ClamAV, Shotwell (just make sure that your permissions are sorted first before getting this to use older settings because anything inaccessible just gets cleared out; F-Spot was never there at first in my case, but it may differ for you), UFRaw, Chrome, Evolution (never have been a user of Mozilla Thunderbird, the default email client on Mint), Dropbox, FileZilla, MySQL Administrator, MySQL Query Browser, NetBeans, POEdit, Banshee (while Rhythmbox is what comes with Mint, I replaced it with this), VirtualBox and GParted. This is quite a list and while I maybe should have engaged the services of dpkg to help automate things, I didn't do that on this occasion, though Mint seems to have a front end for it that does the same sort of thing. Given that the community favours clean installations, it's little that something like this is on offer in the suite of tools in the standard installation. This is the type of rigmarole that one would not draw on themselves too often.
With desktop tinkering and software installations complete, it was time to do a little more configuration. To get my HP laser printer going, I ran hp-setup to download the (proprietary, RMS will not be happy...) driver for it because it otherwise wouldn't work for me. Fortune was removed from the terminal sessions because I like them to be without such things. To accomplish this, I edited /etc/bash.bashrc and commented out the /usr/games/fortune line before using apt-get to clear the software from my system. Being able to migrate my old Firefox and Evolution profiles, albeit manually, has become another boon. Undoubtedly, there are more adjustments that I could be making, but I am happy to do these as and when I get to them. So far, I have a more than usable system, even if I engaged in more customisation than many users would go doing.
Let's finish this with some of my impressions of Linux Mint. What goes without saying is that some things are done differently, which is to be expected. Distribution upgrades are just one example, while there are tools available to make clean installations that little bit easier. To my eyes, the desktop looks very clean and fond display is carried over from Ubuntu, not at all a bad thing. While it may sound like a small matter, it does appear to me that Fedora and openSUSE could learn a thing or too about how to display fonts onscreen on their systems. It is the sort of thing that adds the spot of polish that leaves a much better impression. So far, it hasn't been any hardship to find my way around; it helps that I can make the system fit my wants and needs. That it looks set to stay that way is another bonus. We have a lot of change coming in the Linux world, with GNOME 3 on the way and Ubuntu's decision to use Unity as their main desktop environment. While watching both of these developments mature, it looks as if I'll be happily using Mint. Change can refresh, while a bit of stability is good too.
Turning off the admin bar in WordPress 3.1
25th October 2010
Work on WordPress 3.1 is in full swing at the moment, though I initially thought that they were taking a little break after 3.0. From what I can see, many refinements are being made to the multi-blog functionality and behind-the-scenes work is ongoing on the administration screens too.
Another under-the-bonnet change has been to make WordPress less tied to MySQL, since the possibility of dropping in support for an alternative such as PostgreSQL is now a reality even if it isn't part of the default package. For now, it looks as if this will be plugin territory rather than default multi-database support, though that may become a sensible development in the light of Oracle's acquisition of MySQL and its sabre-rattling regarding Java patents. So far, the change to WordPress has affected my use of its database engine to power an offline version of my online photo gallery, but a quick spot of code editing sorted that issue.
One more obvious alteration will be the addition of a WordPress.com style administration bar to the top of all content and administration screens for a user who is logged into the system. Though it will be turned on by default, there will be the option of turning it off for those among who prefer things that way. All that will be needed for this is to add the following line near the top of wp-config.php:
define( "WP_SHOW_ADMIN_BAR", false);
The chance to see new additions like those above and be ready for is my main reason for following WordPress development. It's best to be ready instead of being surprised, though it has to be said that the blogging or CMS platform is a very polished one these days.
Upgrading to Fedora 13
1st June 2010
After having a spin of Fedora's latest in a VirtualBox virtual machine on my main home PC, I decided to upgrade my Fedora box. First, I needed to battle imperfect Internet speeds to get an ISO image that I could burn to a DVD. Once that was in place, I rebooted the Fedora machine using the DVD and chose the upgrade option to avoid bringing a major upheaval upon myself. You need the full DVD for this because only a full installation is available from Live ISO images and CD's.
Since all was graphical easiness, I got back into Fedora again without a hitch. Along with other bits and pieces, MySQL, PHP and Apache are working as before. If there was any glitch, it was with NetBeans 6.8 because the upgrade from the previous version didn't seem as complete as hoped. However, it was nothing that an update of the open source variant of Java and NetBeans itself couldn't resolve. There may have been untidy poking around before the solution was found, but all has been well since then.
Basic string searching in MySQL table columns
29th April 2010
Last weekend, I ended up doing a spot of file structure reorganisation on the web server for my Assorted Explorations website and needed to correct some file pointers in entries on my outdoors blog. Rather than grabbing a plugin from somewhere, I decided to edit the posts table directly. First, I needed to select the affected observations and this is where I had to pick out the affected rows and edit them in MySQL Query Browser. To accomplish that, I needed basic string searching, so I opened up my MySQL e-book from Apress and constructed something like the following:
select * from posts_table where post_text like '%some_text%';
The % wildcard characters are required to pick out a search string in any part of a piece of text. There may be a more sophisticated method, but this did what I needed in a quick and dirty manner without further ado. Well, it was what I needed.
Removing a column from a MySQL data table
19th April 2010
My trying out WordPress 3.0 in advance of its final release has brought me errors on the management page for website links. After a spot of poking around the TRAC, I found that the bug already has been reported and that the cause is an extraneous column in the *_links table called link_category. The change in taxonomy handling over the years seems to have made it redundant, so I removed the said column from the database using a command like the following from both the MySQL command line and MySQL Query Browser:
alter table database.wp_links drop link_category;
That seems to have made those errors go away, and I hope that their upgrade code takes care of this before WordPress 3.0 is let loose of the general blogging public. Taking out the coding brittleness would do too.
Further securing MySQL in Fedora
4th December 2009
Ubuntu users must be spoilt because any MySQL installation asks you for a root password, an excellent thing in my opinion. With Fedora, it just pops the thing on there with you needing to set up a service and setting the root password yourself; if I recall correctly, I think that openSUSE does the same thing. For the service management, I needed to grab system-config-services from the repositories because my Live CD installation left off a lot of stuff, OpenOffice and GIMP even. The following command line recipe addressed the service manager omission:
su - # Change to root, entering password when asked
yum -y install system-config-services # Installs the thing without a yes/no prompt
exit # Return to normal user shell
Thereafter, the Services item from the menus at System > Administration was pressed into service and the MySQL service enabled and started. The next step was to lock down the root user, so the following sequence was used:
mysql # Enter MySQL prompt; no need for user or password because it still is unsecured!
UPDATE mysql.user SET Password=PASSWORD('MyNewPass') WHERE User='root';
FLUSH PRIVILEGES;
quit # Exit the mysql prompt, leaving the bare mysql command unusable
For those occasions when password problems keep you out of the MySQL shell, you'll find password resetting advice on the MySQL website, though I didn't need to go the whole hog here. MySQL Administrator might be another option for this type of thing. That thought never struck me while I was using it to set up less privileged users and allowing them access to the system. For a while, I was well stymied in my attempts to access the MySQL using any of those extra accounts until I got the idea of associating them with a host, another thing that is not needed on Ubuntu if my experience is any guide. All in all, Fedora may make you work a little extra to get things like thing done, yet I am not complaining if it makes you understand a little more about what is going on in the background, something that is never a disadvantage.
Investigating Textpattern
9th March 2009
With the profusion of Content Management Systems out there, open source and otherwise, my curiosity has been aroused for a while now. In fact, Automattic's aspirations for WordPress (the engine powering this blog) now seem to go beyond blogging and include wider CMS-style usage. Though some may even have put the thing to those kinds of uses, I believe that it has a way to go before it can put itself on a par with the likes of Drupal and Joomla!.
Speaking of Drupal, I decided to give it a go a while back and came away with the impression that it's a platform for an entire website. At the time, I was attracted by the idea of having one part of a website on Drupal and another using WordPress, but the complexity of the CSS in the Drupal template thwarted my efforts and I desisted. The heavy connection between template and back end cut down on the level of flexibility too. Though that mix of different platforms might seem odd in architectural terms, my main website also had a custom PHP/MySQL-driven photo gallery too and migrating everything into Drupal wasn't going to be something that I was planning. Since I might have been trying to get Drupal to perform a role for which it was never meant, I am not holding its non-fulfillment of my requirements against it. While Drupal may have changed since I last looked at it, I decided to give an alternative a go regardless.
Towards the end of last year, I began to look at Textpattern (otherwise known as Txp) in the same vein, and it worked well enough after a little effort that I was able to replace what was once a visitor dossier with a set of travel jottings. In some respects, Though Textpattern might feel less polished when you start to compare it with alternatives like WordPress or Drupal, the inherent flexibility of its design leaves a positive impression. In short, I was happy to see that it allowed me to achieve what I wanted to do.
If I recall correctly, Textpattern's default configuration is that of a blog, which means that it can be used for that purpose. So, I got in some content and started to morph the thing into what I had in mind. Because my ideas weren't entirely developed, some of that was going on while I went about bending Txp to my will. Most of that involved tinkering in the Presentation part of the Txp interface, though. It differs from WordPress in that the design information like (X)HTML templates and CSS are stored in the database rather than in the file system à la WP. Txp also has its own tag language called Textile and, though it contains conditional tags, I find that encasing PHP in <txp:php></txp:php> tags is a more succinct way of doing things; only pure PHP code can be used in this way and not a mixture of such in <?php ?> tags and (X)HTML. A look at the tool's documentation together with a perusal of Apress' Textpattern Solutions got me going in this new world (it was thus for me, anyway). The mainstay of the template system is the Page, while each Section can use a different Page. Each Page can share components and, in Txp, these get called Forms. These are included in a Page using Textile tags of the form <txp:output_form form="form1" />. Style information is edited in another section and you can have several style sheets too.
The Txp Presentation system is made up of Sections, Pages, Forms and Styles. The first of these might appear in the wrong place when being under the Content tab would seem more appropriate but the ability to attach different page templates to different sections places their configuration where you find it in Textpattern and the ability to show or hide sections might have something to do with it too. As it happens, I have used the same template for all bar the front page of the site and got it to display single or multiple articles as appropriate using the Category system. Though it may be a hack, it appears to work well in practice. Being able to make a page template work in the way that you require really offers a considerable amount of flexibility; it allowed me to go with one sidebar rather than two as found in the default set up.
Txp also has the facility to add plugins (look in the Admin section of the UI) and this is very different from WordPress in that installation involves the loading of an encoded text file, probably for the sake of maintaining the security and integrity of your installation. I added the navigation facility for my sidebar and breadcrumb links in this manner, with back end stuff like Tiny MCE editor and Akismet coming as plugins too. While there may not be as many of these for Textpattern, the ones that I found were enough to fulfil my needs. If there are plugin configuration pages in the administration interface, you will find these under the Extensions tab.
To get the content in, I went with the more laborious copy, paste and amend route. Given that I was coming from the plain PHP/XHTML way of doing things, the import functionality was never going to do much for me with its focus on Movable Type, WordPress, Blogger and b2. The fact that you only import content into a particular section may displease some, too. Peculiarly, there is no easy facility for performing a Textpattern to Textpattern migration apart from doing a MySQL database copy. While some alternatives to this were suggested, none seemed to work as well as the basic MySQL route. Tiny MCE made editing easier once I went and turned off Textile processing of the article text. This was done on a case by case basis because I didn't want to have to deal with any unintended consequences arising from turning it off at a global level.
While on the subject of content, this is also the part of the interface where you manage files and graphics along with administering things like comments, categories and links (like a blog roll on WordPress). Of these, it is the comment or link facilities that I don't use, allowing me to turn comments off in the Txp preferences. So far, I am using categories to bundle together similar articles for appearance on the same page, while also getting to use the image and file management side of things as time goes on.
All in all, it seems to work well, even if I wouldn't recommend it to the sort of audience to whom WordPress might be geared. My reason for saying that is because it is a technical tool that is used best if you are prepared to your hands dirtier from code cutting than other alternatives. I, for one, don't mind that at all because working in that manner might actually suit me. Nevertheless, not all users of the system need to have the same level of knowledge or access; usefully, it is possible to set up users with different permissions to limit their exposure to the innards of the administration. In line with Textpattern's being a publishing tool, you get roles such as Publisher (administrator in other platforms), Managing Editor, Copy Editor, Staff Writer, Freelancer, Designer and None. Those names may mean more to others, but I have yet to check out what those access levels entail because I use it on a single user basis.
Txp may lack certain features, such as graphical visitor statistics instead of the current text listings. While, its administration interface could benefit from refinement, it fulfils my core requirements. The more streamlined approach makes it more practical in my opinion, which is demonstrated by my creation of A Wanderer's Miscellany. Consider exploring it yourself to see what's possible, since I am certain that I have only scratched the surface of Textpattern's capabilities.
Running Internet Explorer on Linux
7th July 2008
On first sight, this probably sounds daft given how good Firefox is, yet you cannot ignore those surfing the web using the ever pervasive Internet Explorer when doing some web development. Though using virtualisation is a solution to the need, it can mean that you need to set up a web server with Perl, PHP, MySQL and the like in a virtual machine, all for a little offline testing and then there's the potential for a lot of file copying too. Otherwise, you are trying to sneak things online and catch the glitches before anyone else does, never a good plan.
Therefore, having the ability to run IE to test your offline LAMP set up is a boon, and IES4Linux allows you to do what's really needed. Naturally, WINE is involved, so some flakiness may be experienced, even after the ever useful API library's reaching version 1. Otherwise, all usually runs well once you work your way through the very helpful instructions on the IES4Linux website. I did get a misplaced message about the version of WINE that I was using, and Python errors made a worrying appearance, but neither compromised the end result: a working IE6 installation on my main Ubuntu box.
IE5 and IE5.5 are also on offer if you're interested but, after looking at my visitor statistics, I think that I can discount these. IE7 and the work-in-progress IE8 make no appearance on the availability list. The absence of IE7 is not a big problem as it might appear because coding for IE6 sufficiently suffices for IE7, even now; IE8 may not be the same in this regard, but we shall see. Even so, a later browser release does mean a more secure version, and I reckon that including IE7 should be next on the project's to-do list. Saying that, what we have now is far better than nothing at all.
A collection of lessons learnt about web hosting
28th March 2008
Putting this blog back on its feet after a spot of web hosting bother caused me to learn a bit more about web hosting than I otherwise might have done. Here's a selection, and they are in no particular order:
- Store your passwords securely and where you can find them because you never know how a foul up of your own making can strike. For example, a faux pas with a configuration file is all that's needed to cause havoc for a database site such as a WordPress blog. After all, nobody's perfect and your hosting provider may not get you out of trouble as quickly as you might like.
- Get a MySQL database or equivalent as part of your package, rather than buying one separately. If your provider allows a trial period, then changing from one package to another could be cheaper and easier than if you bought a separate database and needed to jettison it because you changed from, say, a Windows package to a Linux one or vice versa.
- It might be an idea to avoid a reseller unless the service being offered is something special. Going for the sake of lower cost can be a false economy, and it might be better to cut out the middleman altogether and go direct to their provider. Being able to distinguish a reseller from a real web host would be nice, but I don't see that ever becoming a reality; it is hardly in the resellers' interests, after all.
- Should you stick with a provider that takes several days to resolve a serious outage? The previous host of this blog had a major MySQL server outage that lasted for up to three days, and seeing that was one of the factors that made me turn tail to go to a more trusted provider that I have used for a number of years. The smoothness of the account creation process might be another point worthy of consideration.
- Sluggish system support really can frustrate, especially if there is no telephone support provided and the online ticketing system seems to take forever to deliver solutions. I would advise strongly that a host who offers a helpline is a much better option than someone who doesn't. Saying all of that, I think that it's best to be patient and, when your website is offline, that might not be as easy you'd hope it to be.
- Setting up hosting or changing from one provider to another can take a number of days because of all that needs doing. So, it's best to allow for this and plan ahead. Account creation can be quick but setting up the website can take time while domain name transfer can take up to 24 hours.
- It might not take the same amount of time to set up Windows hosting as its Linux equivalent. I don't know if my experience was typical, but I have found that the same provider set up Linux hosting far quicker (within 30 minutes) than it did for a Windows-based package (several hours).
- Be careful what package you select; it can be easy to pick the wrong one, depending on how your host's sight is laid out and what they are promoting at the time.
- You can have a Perl/PHP/MySQL site working on Windows, even with IIS being used in place instead of Apache. The Linux/Apache/Perl/PHP/MySQL approach might still be better, though.
- The Windows option allows for .Net, ASP and other such Microsoft technologies to be used. I have to say that my experience and preference is for open-source technologies, so Linux is my mainstay, but learning about the other side can never hurt from a career point of view. After, I am writing this on a Windows Vista powered laptop to see how the other half lives, as much as anything else.
- Domains serviced by hosting resellers can be visible to the systems of those from whom they buy their wholesale hosting. This frustrated my initial attempts to move this blog over because I couldn't get an account set up for technologytales.com because a reseller had it already on the same system. It was only when I got the reseller to delete the account with them that things began to run more smoothly.
- If things are not going as you would like them, getting your account deleted might be easier than you think, so don't procrastinate because you think it is a hard thing to do. Of course, it goes without saying that you should back things up beforehand.
Sun MySQL and Oracle Bea acquisitions
16th January 2008
While I know what I said about a post every two days, something has entered my head that seems timely. Things seem to starting up for 2008 and my getting a swathe of post ideas is only one of them. Today, Sun has bought up MySQL, the database that stores these ruminations for posterity, and Oracle has finally got its hands on Bea, the people behind the Weblogic software with which I have had an indirect brush for a lot of 2007.