WordPress Bits

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A look inside the WordPress database

Posted by Leonid Mamchenkov on August 8, 2007

Update: This article is also available in Chinese (thanks to Denis).

WordPress, as most other modern content management systems, is a very database-centric application. It keeps all information in the database – blog settings, posts, comments, links, users, etc. Therefor it is important to understand how the database is organized, what types of data is stored there, and how different things are linked to each other.

But before we dive into it, here are three points that I want to stress out:

  1. WordPress API provides a number of ways to manipulate data without directly accessing the database. So, technically, you don’t have to know how the database is organized. However, if you do, you’ll probably find solutions to your problems faster, and they’ll be easier to implement.
  2. WordPress database scheme is small and simple. There is nothing to be scared of. It’s only 10 tables, with just a few fields each. Overall, the scheme makes so much sense, that you will probably keep most of it in mind after a second look at it, even though you don’t have to.
  3. WordPress database scheme is well documented. The only thing with that Codex page is that it explains tables in alphabetic order, which makes sense when you are looking up something. But for the first few times, it’s better to have a different order, which is what this post is trying to achieve.

OK, now let’s see what is there to see.

For the rest of the article, you’ll need either another browser tab with previously mentioned database description at Codex, or a database tool, such as PHPMyAdmin or MySQL command line. To find a list of database tables in your WordPress installation run “SHOW TABLES” query. To get a specification of any table use EXPLAIN command, like so: “EXPLAIN wp_posts“.

wp_posts

WordPress is mostly used as a blogging engine content management system (CMS, for short). So, the “content” table, I think, is of primary importance. Pages, posts, and attachments are all content. And WordPress keeps them all in one table – wp_posts.

Actually, attachments are kept as they are – files on disk, but WordPress uses wp_posts table to keep attachment meta information, such as ID of user who uploaded it, ID of post to which the attachment is linked, the date it was uploaded, etc.

Pages, posts, and attachments can be very similar and they can be very different. For now, we want to look at things which are common between them. All three have a unique ID (usually generated by WordPress or MySQL automatically), an author (person who wrote the post or uploaded the file), posting date, title, and description (even if empty, there is still a way to add it and use it later). All three have an URL. So, for each post, page, and attachment, WordPress keeps a record in wp_posts table.

Now, there are a few ways that posts, pages, and attachments differ. To differentiate between them, WordPress uses a column post_type in wp_posts table. For posts, the value of post_type is ‘post’. For pages – ‘page’. For attachments – ‘attachment’.

Then, there are a few columns which are used only when post is of some specific type. For example, column post_mime_type is used to keep attachments file types, such as ‘image/jpeg’ and ‘application/pdf’ (read about MIME at Wikipedia). Column menu_order is used to specify the order of pages. Column post_parent is used to organize pages with sub-pages, as well as to link attachments to posts.

To get a better picture of how and when each field is used, take a look at real records for each post type:

  • SELECT * FROM wp_posts WHERE post_type = ‘post’ LIMIT 1
  • SELECT * FROM wp_posts WHERE post_type = ‘page’ LIMIT 1
  • SELECT * FROM wp_posts WHERE post_type = ‘attachment’ LIMIT 1

If you are using MySQL command line tool, then you will appreciate a “\G” at the end of the query (“SELECT * FROM wp_posts WHERE post_type=’post’ LIMIT 1 \G”). It will give you the results in a slightly more readable format.

Post status is also kept in this table. In most cases you’ll see ‘publish’ for published posts, ‘draft’ for drafts, and ‘inherit’ for attachments. But there are a few others that you can learn from the table specification.

Here are a couple of ideas for you on what you could do with just wp_posts table:

  • Generate some statistics – how many posts are there in total, how many posts of each type, how many posts each author published, what is the average number of posts published per day over a period of time, etc.
  • Generate a list of all attachments
  • Generate an image gallery for each post (hint: “WHERE post_type = ‘attachment’ AND (post_mime_type = ‘image/jpeg’ OR post_mime_type = ‘image/gif’ OR post_mime_type = ‘image/png’)“).

wp_postmeta

There are probably a million of things that you’d want to keep about some of your posts – the mood your were when wrote it, the song you were listening at the moment, the geographical location you were at, some list of related links, post-specific information for search engines (SEO), and so on, and so forth. All these things go into wp_postmeta table.

The structure of this table is very simple and flexible. It has only four columsn: meta_id, post_id, meta_key, and meta_value. meta_id is automatically generated and I can’t think of a scenario where you would want to change that – there are many other fun things to do. post_id is the ID of the post (as in record from the wp_posts table) to which current meta information is linked. meta_key is the description of the information that you want to attach to the post (such as ‘mood’ or ‘song’). meta_value is the actual content of the meta information (such as ‘Grumpy!’ or ‘The WordPress Song.mp3′).

WordPress uses this table to store additional information about attachments, which does not fit into wp_posts table (file system path to the attachment, thumbnail information, if any, etc). Also, this table is used to store custom field names and values – those that you see in the box under your post editor. And, of course, there are tonnes of plugins out there which utilize this table for their own needs. So, if you decide to use this table in your plugin, make sure that you come up with some unique names for your meta keys. Otherwise, your plugin might interfere with some other plugin and you’ll get some really weird and totally unexpected results.

wp_users

WordPress uses this to store registered users. User ID, login, encrypted password, full name, registration date, and things like that are kept in wp_users. Think of it as essential information about the users.

wp_usermeta

The wp_usermeta table for users is exactly what wp_postmeta table is for posts. You can keep all sorts of things for each registered user here – personalized blog settings (WordPress already does so for visual editor preference, for example), birthdays, contact information, etc.

wp_comments

wp_comments table keeps all comments for your site. These include all approved comments, comments awaiting moderation, SPAM comments, and even trackbacks and pingbacks which are sent to you from other web sites. You can probably guess most of the columns in this table without me telling you. But just in case, here are the ones you probably care about:

  • comment_ID – unique ID of each comment, automatically generated by MySQL
  • comment_post_ID – ID of the post for which the comment was made
  • comment_author – name of the comment author
  • comment_author_email – email of the comment author
  • comment_author_url – URL of the comment author
  • comment_author_IP – the IP that comment author came from
  • comment_date – the data and time the comment was made
  • comment_content – the actual comment
  • comment_approved – whether the comment was moderated, and if yes, then how
  • comment_agent – browser signature of the commenter (MSIE, Firefox, Safari, etc)
  • comment_type – if it is a regular comment, or trackback , or something else
  • user_id – if comment user is a registered user, you’ll have his ID in here

There are a couple of other fields in there, but we’ll leave them for now, as we did with other tables.

wp_options

As we saw in update to “Quick access to WordPress options” post, wp_options is the table that holds all the global options for your WordPress installation. The core of this table is very similar to the wp_postmeta and wp_usermeta tables. And it is understandable – wp_options stores information about your WordPress in much the same way, as wp_postmeta stores information about posts and wp_usermeta stores information about users. However, you will probably notice a few extra columns.

blog_id column is there, but it is not of much use on a standalone WordPress installations. It is used only by WordPress MU. Regular WordPress and WordPress MU share most of the source code and database structure. So, WordPress MU uses blog_id column in wp_options table to differentiate between options for different blogs under one roof.

autoload column controls if the option is always loaded from the database and cached for use by WordPress and plugins or if it is read only when asked for. Most options that I’ve seen, are autoloaded.

wp_categories

If you have any categories in your WordPress installation, wp_categories is the table that keeps those records. Category names and descriptions are stored here, as well the ID of each category’s parent.

To work faster, WordPress often keeps aggregated values in the database, instead of recalculating them each time. For example, frequently requested counts of posts and links in each category are simply stored in the wp_categories table (WordPress uses the same set of categories for both links and posts). Every time you add post to a category, the post counter (column category_counter) increases. Every time you remove post from the category, the counter decreased. Same goes for links (column link_count). That’s why you see those extra columns in the table.

wp_post2cat

Linking posts to categories is done via wp_post2cat table. This is a standard approach for many-to-many relationships in relational databases. Thewp_post2cat table has only three fields: the unique record ID (automatically generated), the ID of the post, and the ID of the category to add the post to.

wp_links

Usually wp_links table is used to store the blogroll – web site’s list of links. Check the blogroll administration interface carefully, and you’ll see lots of options, which aren’t used by most WordPress users (no statistical proof here though). All those links options can be stored in wp_links table. In fact, you won’t need to write much code to turn WordPress into a link directory, like Yahoo! once was. It’ll be only a matter of an appropriate theme.

One important bit to notice here, is that link_owner is kept for each link. So, you know who created the link.

wp_link2cat

wp_link2cat table is the exact copy of wp_post2cat, except it keeps the ID of the link, instead of the ID of the post.

That’s all there is to WordPress database structure. If you see any other tables in your installation, then they were probably added by one of the plugins that you’ve installed.

Update: Those of you who prefer a bird’s eye view, will appreciate WordPress Database Structure (PNG file, 167 KBytes, from here).

Update: Ryan Boren has posted an explanation of database changes in WordPress 2.3 related to taxonomy – a new way of tagging and categorizing posts and links.

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95 Responses to “A look inside the WordPress database”

  1. ia said

    This is great. This page has some examples but is not up-to-date. It’s worth noting how WP differentiates pages from posts in the database. I needed that info when I was updating to the latest version just now—all the pages became posts! :)

  2. sheida said

    good job

    it is really needed to know exactly what is going on
    I figure out while playing with database, there were no tutorial for that

  3. ia,

    Thanks for the link. It has some good descriptions of what’s going on, but it is, if I understand correctly, very outdated. It covers WordPress 2.0, while the most recent version of WordPress is 2.2 (OK, 2.2.2). And 2.3 is coming out shortly, from what I here.

    It seems that before, WordPress used post_status to differentiate between posts and pages. In the example on that page, it mentions post_status = ‘static’, and post_type is not set in all example records. This is not so in WordPress 2.2.2.

    Anyway, it’s good to have a few documents around, when trying to figure this stuff out. So thanks for the link once again.

  4. Sheida,

    thanks.

    A lot of interesting stuff can be done with direct database access and with WordPress Database class (wpdb), so we’ll sure be coming back to this subject more in the future.

  5. [...] A look inside the WordPress database – A great explanation – makes that codex article come alive. [...]

  6. munggur said

    Agree with you. It’s all about database. One interesting thing is that using the data, WP can make big ‘collective knowledge’, show stats and relate each post (with comments) to other post.

    After all, each of user can even download and upload their data (posts and comments and etc.) in .xml format. Great job. WP!

  7. [...] A look inside the WordPress database WordPress, as most other modern content management systems, is a very database-centric application.  It keeps all […] [...]

  8. Ineation said

    Excellent Post (and blog).
    Indeed I do really think that wp Db is very simple BUT very flexible.
    One of the most exciting thing is in the post table. The fact that you can deal with other kind of objects (page, attachment, but you can easily imagine others) is very powerful if you want to customize and adapt the application for your need without adding a new table. The question is : should we integrate as much custom object in existing tables or would it be safer that plugins deals with their own tables ? (I guess the answer is “it depends !”).
    Bye alls.

  9. Ineation,

    indeed. The thing to remember here is that WordPress own things come with certain logic attached to them. Such as: pages can inherit each other, pages can be ordered, posts can be organized into categories, etc. If the things that you do from your plugin follow any of these logic, than you better use WP internal stuff. If not – than your own tables, and your own logic.

  10. Mikael said

    Great post and a great blog!
    Found lots of interesting thoughts and facts here..

    Keep up the good work Leonid!

  11. Thanks Mikael. Will try to ;)

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  13. Thanks for this invaluable post, it complements/extends nicely the available literature on WordPress DB.
    You have managed to create a very interesting and useful site for all “technically” inclined WordPress users who want to know “What is going under the hood” and to furtherly modify – enhance their WordPress experience.
    Thanks for the great articles and wishes for the best.
    As Michael said keep up the good work ;-)
    WordPress Bits deservedly earned a place in my RSS feeds and took the liberty to add this post to StumbleUpon – Hope I didn’t cause any problem with the additional traffic :-)

  14. [...] today I found  A look inside the WordPress database at WordPress Bit through WP dashboard , an excellent complement to official WordPress DB Description in WordPress [...]

  15. Nick,

    thanks for the kind words.

    Feel free to promote the blog all you want – the traffic is not a problem, as the blog is hosted on WordPress.com . I bet it can easily handle Slashdot/Digg/Reddit and other effects of the modern web (hint, hint) ;)

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  17. [...] WordPress – A look inside the WordPress database [...]

  18. Murk said

    I’m really pleased to have found these pages at the beginning of the series on hacking WP. (I’m pretty computer literate, but from the days of pascal and Fortran – php and sql passed me by).

    I’d love to be able to write a plugin which would be able to return (one at a time) the next and previous posts which share a category with the current post.

    e.g.

    and to do the same for dates (depending upon context). (Each post title would be visible)

    I’m hoping to learn enough to do that… I’m not holding my breath though!

  19. Murk said

    The other plugin I want to do is ‘remember my activated plugins’. So that as an upgrade takes place you can simply click ‘remember’ then ‘disable’.

    After the upgrade, one would click ‘recall’ and it’d activate the plugins one at a time, alerting the user to any problems. This seems tricky to me!

  20. Murk,

    one of the best ways to learn is to look at other people’s code and try to make your own. There are plenty of pluginsn available already, which do all sorts of things with pages, posts, and categories. Get your hand on some of the simple ones and work your way through. It aren’t that difficult – the main issue is to get familiar with functions that WordPress has for manipulating this data.

    Regarding the “remember plugins” plugin – I think this is or will shortly be done in WordPress itself. I remember I saw some code floating around.

  21. Paveo said

    Thanks, it helps me understand more.

  22. Denis said

    Hi Leonid,

    Can I translate your posts to Chinese?

  23. Denis,

    yes, of course, by all means, please do. :)

    Send me the URL when you’re done, so that I could link to the translation from here.

  24. [...] A look inside the WordPress database « WordPress Bits La base de datos de WordPress mirada por dentro. (tags: wordpress database reverency) Archivado en: Links Diarios   |   Etiquetas: No Tags. [...]

  25. [...] today I found  A look inside the WordPress database at WordPress Bit through WP dashboard , an excellent complement to official WordPress DB Description in WordPress [...]

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  27. Denis said

    Hi Leonid,

    Here is my Chinese Version of your post:

    http://fairyfish.net/2007/08/11/wordpress-database-intro/

  28. Denis,

    Thanks a lot of translating it. I’ve updated the post and now there is a link to your translation at the top.

  29. [...] 这个系列教程翻译自:A look inside the WordPress database。由于原文比较长,我把它分成一系列教程,今天第一篇是开篇介绍。 [...]

  30. [...] A look inside the WordPress database « WordPress Bits [...]

  31. [...]     http://wpbits.wordpress.com/2007/08/08/a-look-inside-the-wordpress-database/ [...]

  32. hello , i have a small problem. i was editing onw of my posts and i have deleted part of it and saved it by mistake, so now part of my post is missing. and i did not keep a copy on my computer. is there a way to find the old information of my post on the database of wp.
    and if yes, how?

    thanks

  33. Pascal,

    no. It’s gone now.

  34. I know this is a pretty old post, but I need some help. I was upgrading my blog to the latest WordPress version, 2.3.1, and now I can’t create or edit posts. I get this message:

    WordPress database error: [Table 'superbt_wordpress.wp_post2cat' doesn't exist]
    SELECT cat_ID AS ID, MAX(post_modified) AS last_mod FROM `wp_posts` p LEFT JOIN `wp_post2cat` pc ON p.ID = pc.post_id LEFT JOIN `wp_categories` c ON pc.category_id = c.cat_ID WHERE post_status = ‘publish’ GROUP BY cat_ID

    Warning: Cannot modify header information – headers already sent by (output started at /home/superbt/public_html/wp-includes/wp-db.php:160) in /home/superbt/public_html/wp-includes/pluggable.php on line 391

    My database doesn’t have the post2cat or the categories tables anymore. I never messed around with my database, so I’m not sure how this happened. Is there any way I can recreate those? Please email me – thank you so much. :)

  35. Tay,

    it looks like either your upgrade didn’t go through completely or some of your plugins are outdated. Try disabling all plugins and checking if you still get the error. If you still have it, something is wrong with your upgrade and you better redo it. Otherwise, enable plugins one by one to see which one causes the problem. Probably there is a newer version of it to which you can upgrade.

  36. Miyijura said

    Tay, thats because wordpress 2.3 change the categories, post2cat and link2cat for terms, term_taxonomy and term_relationships.
    Good luck fixing that!

  37. WTJ said

    i’m using wp 2.3 now. I upgraded from wp 2.2 to 2.3, and I encounter a big problem.

    When I preset a post to be posted on 10th february, then i reedit the timestamp to post on 18th feb, however the post won’t post on 18th feb, but still published on 10th feb (but in the public post, the date is written as 18th feb)

  38. WTJ,

    make sure that “Modify Timestamp” checkbox is checked when changing the date. If you still have the problem, you should probably ask in the Support forums or report a bug to WordPress developers.

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  40. naturalhorsetrainer said

    Hi,

    I’m trying find a way to export blogroll out of wp_links for one domain, and import into another domain with link categories intact from domain to domain.

    I’m hitting a stumbling block on the FK constraint on the wp_term* structure on both sides and am now wondering why the wp_links category structure is wrapped up into the taxonomy for the rest of the WP installation instead of using the link_category field in the wp_link table?

    My choices either seem to be to wipe multiple installations and start over with every link I ever want up front, or input blogroll links by hand on 14 installations… when a simple mysql export/import would do the job otherwise.

    I’m using different categories in the blogroll for my sites, friends sites, business links, and keyworded text links… right now I have 48 links x 12 sites (576 manual edits on top of the original 48) I have to either input one link at a time, or edit one link at a time to change categories…

    Is there a way to remove the foreign key links and work totally within the wp_links table? Why was it done this way? Has anyone come up with a nice way of working around this?

    Thanks in advance :)

  41. naturalhorsetrainer said

    I’m sorry, they are Rev 2.3.x installations.

  42. [...] A look inside the WordPress database [...]

  43. chrisber said

    I am a relative newcomer to all of this, so please be kind if I’m way off base with something. I’ve created several static pages on my site, and it is my understanding that they appear in order based on the post ID in wp_posts. Is there a safe way to edit these ID’s to alter the order of my pages? I assume that I would want to pick a new sequence of numbers starting 1 increment above the highest existing ID? Are there potential dangers that I am unaware of, or will my foolish actions bring about the end of the world as we know it?

  44. Chrisber,

    when you edit the page, there is something called “page order”. It’s one of those boxes on the right. You can put a number there and then use this number to sort the pages. The actual way your pages appear (including the sorting) is controlled from the theme.

  45. chrisber said

    Thanks!

  46. So is this totally out of date now. I am trying to write a plugin that will automatically generate categories and I see that my database contains wp_terms instead of wp_cat** . The other thing is there a set of public functions that I can call to generate a category instead of tweaking the database. Any help would be apreciated wince I am new to the WP world

  47. Talker said

    Hi,
    Am getting close to being comfortable with the crazy switch from ver 2.3.3 to ver 2.5. Now need to find out “how” to address “all” of a given blogs posts. I can access them through categories, but not all the actual posts “in” that blog show up for linear viewing, start to end. Am missing in setting up the address to access the complete blog! Hate being a “newbie” at anything, but thats what I am with WordPress.

  48. Hi,

    can anyone help me please? I paid a designer to do some work on my website http://www.indialogue.info I asked him to then upload the files to the domain name, which he promised to do. I just discovered that the site is still on his server at the address indialogue.gereby.com He just changed the domain indialogue.info to point to his server. This was not our agreement, he was to design the site and put it up to my host. Despite 2 months of phone calls and emails to him, he will not contact me. I cannot retrieve the files from him. I am stuck, because I put in a lot of time and effort into making the site, all the links, the text, the content, the layout was my effort, I just got him to edit the CSS stylesheets for me. So my question is, is there a way I can download the entire site including mysql and put it up myself? Or am I going to have to go the legal route here? Does anyone have previous experience with designers stealing your content and not providing files? And what did you do in such cases?

    Thanks!

  49. [...] Eine weitere Übersicht über die DB-Dinge von WordPress sind hier ersichtlich. [...]

  50. untukita said

    I like it, u explain with so detail. Maybe you can update with the latest version 2.6 ?

  51. Jefferey said

    I just wish there was a way from within the wordpress program to disable the storage of comments marked spam….!

    Oh well in the mean time, here is a PHP file I made to clean up the spam!

  52. clarissa said

    Yes, this “clarrifies” a lot of good hints. Well done!

  53. Alex said

    I have need to create multiple WP sites using (1) database, can this be achieved?
    It seems that by default WP wants to do its own creating of tables in database risking
    the over right of existing info. Please confirm if there is work-a-round to house (1)
    database with several different WP sites.

    Thanks in advance..

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  55. Pascal said

    Hey,
    unfortunatly it seems, the db structure had changed (to its worse in my opinion) in version 2.6

    It would be really nice if you could udate this article or even write a new one because you way of explaining this stuff is easy to undestand and it helps getting more into it.

  56. Karim said

    This is great but not up to date because when I upgrade to version 2.6 from version 2.0
    Database has many changes so I have lost some in my frontend

    it will be nice if you just compare this article with the database of version 2.6

  57. bof said

    as of Word Press 2.3, this article is obsolete

  58. Hendry Lee said

    Thanks. That’s really helpful but is it possible if you update this to the latest version of WordPress, or perhaps for 2.7?

  59. [...] WordPress Bits today posted an interesting article (among all its interesting articles) to show you how you can get started getting to know WordPress inside out. That is, its source code. Also worth reading is last week’s post on WordPress’s database. [...]

  60. JBucknoff said

    Re: WordPress Categories>/b> do not display.

    I’m having a problem displaying more than one category on my WordPress blog. From some of the other message boards I’ve read, I can see that other people are having a similar problem.

    I go to the admin Dashboard and open the Categories page. I can add new categories and sub-categories here, but they never show up on the blog page. I am able to edit the original (“uncategorized”) category to another name, but that is all.

    I “repaired” all of my MySQL tables, as suggested, but this didn’t help. By the way, I don’t see a wp_category table in my database (described in some older documentation), but I do see the name of my (missing) category in the wp_terms table as well as the description of the (missing) category in the wp_term_taxonomy table.

    These are the 10 tables in my MySQL database:

    wp_comments
    wp_links
    wp_ptions
    wp_postmeta
    wp_post
    wp_terms
    wp_termwp_relationships
    wp_termwp_taxonomy
    wp_metadata
    wp_users

    I think I’m using 2.7. I installed it through the GoDaddy interface.

    Can anyone help me? Thanks !!!

    Jerry Bucknoff
    PM Best Practices

  61. Sarah said

    Hi Jerry. I’m somewhat new to WordPress, however I might have a solution / test for you. You will need to have a Post and check the Category for the Category to be listed and visible on the live site. So make some test posts, check your category, and then see if the Category List become live on your blog.

  62. Спасибо за ответы на все вопросы :) Действительно узнал много нового. Вот только до конца так и не разобрался что и откуда.

  63. Has anyone come up with a way to import subscribers into their WordPress wp-users table? The description of the user_status and password fields are a little vague, but other than that, it looks like I can just import these using a database script.

  64. Thank you very much for this post!

    I was using the codex, http://codex.wordpress.org/Database_Description , to compare against my tables, to see if any had become corrupted, and noticed the following problem relative to my wp_posts table:

    The codex states that one of the indexes for this table is post_parent, but my table has post_content indexed instead? Is my table in error, or is the codex in error? I would think that the codex is correct, since post_parent makes more sense as an index, but I am reluctant to just change it on my own.

    If it really should be post_parent instead of post_content, how do I best make the change, using phpadmin?

    Thanks again for the post. Looking forward to your help.

  65. Thanks for this interesting article, I was wondering if cross-reference table could improve database performance ?

  66. ipsg007 said

    the information is very descriptive and surely gonna help me in my project..
    thanks mate..

  67. Thanks a lot this post is very helpfull… I did not get at first what postmeta was for…

  68. You know, even if this is outdated in the face of continuing WP updates, it certainly helps to get a good idea of what a good blog structure looks like. Thanks for the post.

  69. Vatsala said

    Here is a link to the relatively new WP2.7 schemaimage

    But they’re already talking of WP2.8..

  70. [...] Jun.24, 2009 in All, Technology, WordPress Almost two years ago I wrote a blog post titled “A look inside the WordPress database“.  While a lot of people enjoyed it (and, apparently still do, even though it’s a bit [...]

  71. Ayushi said

    Hello all………
    I am new to wordpress….
    And I am having problem with my database….
    Actually I m unable to find my wp_category table in database……
    So I request u all to help me out from this……

  72. Pedro said

    Hello, nice that you have a template just like mine…

    Well, I am trying to resolve a problem of my site, the search form does not seem to work.

    I have tryed several solution I have seen online to edit mysql but for now, none of them has worked.

    can you give me a possible solution please.

    Thanks

  73. [...] Источник, перевод. Смотрите также SEO руководство по поисковой оптимизации блога на WordPress [...]

  74. [...] A look inside the WordPress database [...]

  75. [...] bit more technical information about what’s in your database, from the WPBits blog. November 1st, 2009 | edit(' | ', 'Edit this post', [...]

  76. [...] Database Image: http://wpbits.wordpress.com/2007/08/08/a-look-inside-the-wordpress-database/ [...]

  77. Hi,
    When can we expect the updated version for database 2.7?

    The blog is very useful.. Thanks

  78. ayaba25 said

    it is a cool look into the wp database

  79. garywed said

    Hi All.
    Interesting article, which brings a question to mind. I’m a relative newbie to WP but have done a fair amount of PHP and SQL programming.

    What is the best way to add a new field to a WP table? Direct access or does WP offer functions to accomplish this. For example, let’s say I was setting up a blog where each post was a description of an ornamental plant. And let’s say that for each post, I’d like the wp_post table to contain additional entries for plant common name, scientific name, plant family, geographic area of origin, etc. Since these would be found on each (or at least most) posts, it makes sense to just extend the wp_posts table to include this data.

    What is the best way to do this? Direct access? WP function? Or new, custom database, perhaps using the permalink as a primary key?

    Thanks.

    • webmaster said

      Hi Garywed I am wanting to develop a WordPress application exactly along the lines you describe. Have you sorted this out? If so would be interested to hear from you directly : rosenthal(add atsign)iafrica.com

  80. [...] via A look inside the WordPress database « WordPress Bits. [...]

  81. [...] http://wpbits.wordpress.com/2007/08/08/a-look-inside-the-wordpress-database/ [...]

  82. Excellent summary, very helpful

  83. stiller said

    I stumbled across the database diagram of version 2.9.1 the other day from an online db schema editor. It allows schema editing by any collaborators.

    I added some missing pieces and hope you guys would find it useful. Not sure if any people would care enough to update it regularly though.

    Here is the link to the diagram: http://schemabank.com/p/5Lj5F

  84. Where is the theme template path(url) stored?

  85. ian said

    i am a newbie to wordpress so please excuse the lack of knowledge.

    but how do i make a database page similar to this but in wordpress?

    https://www.heroprint.com.au/default.asp?ID=P0058&content=Specification.asp?ID=P0058&frm=MainMenu

    Thanks, Ian

  86. Excellent summary, very helpful

  87. murthy said

    very useful, detailed and understandable article

  88. I was just doing some research into the architecture of the WordPress DB and this got me headed into the right direction. Thx, Richard

  89. [...] we look at an explanation of the WordPress database (here or here), it is obvious that, while it isn’t the most complex database, the process of [...]

  90. there have to be a tutorial about wordpress database and how to manage it , anyways ,very usefull topic .i look for more deeply topics like this

  91. [...] entrar directamente a la base de datos de WordPress, aunque sí puede ser interesante leer esto (A look inside the WordPress database), complementado con la documentación actualizada del esquema (WordPress Codex: Database [...]

  92. Eman Khan said

    Hello Nice and amazing Information of wordpress. This is quite good and easy to understand what in the background going on…

  93. [...] links, users, etc. Therefor it is important to understand how the database is organized…CLICK HERE to read [...]

  94. Jacs said

    Hi there, thanks for this information, very useful. In my website, some of my BG images aren’t showing and I have been told there is a problem with my database in the WP_options table. I have no idea what line and the host can’t help me. I’ve been trying to resolve this for weeks – http://www.test.cwscambodia.org/

    See my full post at – http://wordpress.org/support/topic/background-images-missing?replies=2#post-2719051

    Any ideas from an expert?

    Thanks in advance :)

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