Converting Tags To Categories In WordPress

Update
Spent the last two days working furiously, integrating more plugins, checking whether they work, throwing exceptions, adding Google AdSense ads, et al. Which reminds me, I wanted to add Yahoo! Publisher Network ads – apparently, they pay more, allow you to receive payments via PayPal, and even let you add ads to PDF files and RSS feeds – BUT, and this a big pain in the butt, they want US-based publishers only with predominantly US-based traffic (otherwise, they even ban people…brr).

The Error
One problem I encountered immediately after shifting was using the ‘Convert Categories to Tags’ feature in WordPress. Hadn’t used it on WordPress.com hosted blogs earlier, so I was shocked to see that it DID copy all categories into tags – but at the same time, it deleted those categories too. Hell, those posts didn’t even come under the default category, they simply went off the radar. Since it was a time when I was doing multiple changes to my blog per day, I hadn’t bothered to take a minute-by-minute database backup. I had nothing to fall back to. No problem, I thought, other people must have faced the same problem, and there must be SOME script / plugins out there to handle the conversion of tags back into categories. Surprisingly, there weren’t any.

The Solution
Spent the rest of the day trying to figure out the WordPress database, and a few trials (and a some backup restores later), I hit upon a way to do it.

1. If there are any existing categories which are named exactly the same as any tags, delete them from Manage > Categories on your WordPress dashboard. The only reason I say this is because it’ll save you a lot of headache while editing the database.
2. First thing, whenever you do ANY sort of mucking about with databases – back it up! On hosts like GoDaddy, you’ll have an option in your hosting manager to create an SQL dump; otherwise, open up your database manager (on the server) and choose the Export option.
3. Login to your database manager – which would be phpMyAdmin generally. You’ll need to use the username and password you created initially for this. Generally, the username could be the same as your database name. In case it isn’t, you should’ve written it down, dum dum. :p
4. Open the database related to WordPress and open the table wp_terms_taxonomy. Check phpMyAdmin’s documentation if you don’t know how. Explaining that is not my job.
5. Check the box next to any fields which are marked as post_tags, leaving the category and link_category fields as it is. Then, click on the Edit icon at the bottom of the table.
6. Replace post_tags with the text category in the Edit page. No other change is necessary. Submit the form.
7. If you run into a MySQL error, of the sort – ‘xx-category already exists’, where ‘xx’ is a number – that has happened because a category and a tag have the same name, and therefore that particular post_tag can’t be renamed to its equivalent category field.

That’s that! Login back to your WordPress dashboard, and you’ll find that all categories have been restored using the tags which were created. Personally, on WordPress, I feel that the categories feature is better than tagging – at least presents a list to choose from! Tagging, on the other hand, doesn’t have auto-complete (by default, at least) on WordPress.

And frankly, WordPress’ categories to tags converter sucks – first, erasing categories, and then not even warning the user before doing so.