Introduction to Wordpress Database: wp_users
Current Version : 2.9.2
Wordpress saves the user details in wp_users table. All the major details like user id, user_login, email address, password (In MD5) are saved in this table.
Below mentioned is the structure of this table:

Field
Type
Null
Key
Default
Extra

ID
bigint(20) unsigned

PRI
NULL
auto_increment

user_login
varchar(60)
IND

user_pass
varchar(64)

user_nicename
varchar(50)

IND

user_email
varchar(100)

user_url
varchar(100)

user_registered
datetime

0000-00-00 00:00:00

user_activation_key
varchar(60)

user_status
int(11)

0

display_name
varchar(250)

Indexes

Keyname
Type
Cardinality
Field

PRIMARY
PRIMARY
1
ID

user_login_key
INDEX
None
user_login

user_nicename
INDEX
None
user_nicename

here, password is  MD5 encrypted.
We manually are not supposed to make any entry in this table. However, you can use this function in your template or plugin:
wp_insert_user()
This function requires an array of data to be inserted for the user. Please check more details here …

Introduction to Wordpress Database: wp_usermeta
Current Version: 2.9.2
In general, wordpress saves many user related data. It is difficult to save them in one column in wp_users. Hence Wordpress saves these data in wp_usermeta table. The structure of this table is mentioned below:

Field
Type
Null
Key
Default
Extra

umeta_id
bigint(20) unsigned

PRI
NULL
auto_increment

user_id
bigint(20) unsigned

‘0′
FK->wp_users.ID

meta_key
varchar(255)
Yes
IND
NULL

meta_value
longtext
Yes
IND
NULL

Indexes

Keyname
Type
Cardinality
Field

PRIMARY
PRIMARY
9
umeta_id

user_id
INDEX
None
user_id

meta_key
INDEX
None
meta_key

In this table, we need to add following details:
user_id -> user_id of the user
meta_key -> a unique key for the user data
meta_value -> the actual data to be saved.
Wordpress provides following functions to manage this table:
get_usermeta($userid, $metakey )
$userid
(integer) (required) The ID of the user …

Introduction to Wordpress Database: wp_options
Current Version: 2.9.2
Wp_options tables is used to store wordpress’s default settings, standard options etc. The structure of the table is as follows:

Field
Type
NULL
Key
Default
Extra

option_id
bigint(20) unsigned

PRI Pt1
NULL
auto_increment

blog_id
int(11)

PRI Pt2
0

option_name
varchar(64)

PRI Pt3 & IND

option_value
Longtext

Autoload
varchar(20)

Yes

Indexes

Keyname
Type
Cardinality
Field

PRIMARY
PRIMARY
184
option_id
blog_id
option_name

option_name
UNIQUE
184
option_name

This tables is used by wordpress to save  standard options, like blogurl, blog title, description, admin email address, rewrite rules etc.
This table is very useful for plugin and theme developers. A developer can store his own standard options in this table.
How to save data in this …

Image Editor
In WordPress 2.9 whenever you upload an image, you can edit it using the edit image option.

The image editor contains several useful functions such as image cropping, image rotation and image flipping. In addition, you can also undo and redo your actions.
Post Trash Can
Wordpress 2.9 provides a very useful feature, called Post Trash Can. We all are very well aware of this feature and we use it for emails. However, you can use this feature for posts and comments from wordpress 2.9.
wp2-92
The new Trash feature completely replaces the …

Custom fields provide  a strong tool for developers to make it more user friendly and customizable.
Today, we will see how we can assign an expiration date to a post, so the post will disappear after a particular date:
1)      Change the default loop in your index.php file as mentioned below:

2)      Now, when you add/edit a post, add a custom field expiration and assign the date as value(with the format mm/dd/yyyy 00:00:00). The post will disappear after that date from the home page.
Note that if you do not assign …

Introduction to Wordpress Filters
What is a Filter?
Filters are functions that WordPress passes data through, at certain points in execution, just before taking some action with the data (such as adding it to the database or sending it to the browser screen).
Filters passed data between database and browser. Most inputs and outputs in wordpress need to pass through at least one filter.
You can add your own filter to a plugin or theme for special purpose.
The basic steps to add your own filters to WordPress (described in more detail below) are:

Create …

Check WordPress ?lugin Compatibility before Upgrading
Now, wordpress users can check if the plugin is compatible with their wordpress version before installing the plugin itself. This feature is in testing (Beta) and has been implemented for several plugins in the wordpress directory.
You can check this for any version of wordpress and the plugin itself. Check the screen capture here:

What is podcasting?
Podcasting is distributing audio or video content via RSS 2.0, or Atom. Podcast clients such as iTunes, Juice, or CastPodder(linux) allow listeners to subscribe to your RSS/Atom feed and automatically download your content to their portable audio players as it becomes available.
Podcast in Wordpress: (wordpress.com)
Create audio or video that you want to share (usually MP3 or MP4)
Upload the file to a server
Link to the file in a post in your weblog
Wordpress automatically Includes a link to the file in your RSS/Atom feed
Listeners

After the Deadline, Language Checking Software Used by WordPress is Now Open Source
If your blogging platform of choice is WordPress, then you’ve no doubt noticed recent improvements to the way it catches spelling, style, and grammatical errors. That’s thanks to acquisition of After the Deadline, a language checking software package designed for WordPress and TinyMCE.
The plugin’s creator, Raphael Mudge, announced today that he has released the source code for After the Deadline (AtD) under the GNU General Public License. “We

What is a wordpress theme framework?
A theme framework is a theme that is designed to be a flexible foundation that can serve as a parent theme for building child themes. The use of theme framework may ease theme development by reducing the volume of work which may be needed in creating a backbone for your theme.
Available Frameworks

Sandbox (Scott’s page)
Thematic (Ian’s page)
WP Framework (Official page)
Hybrid (Official ?age)
Carrington (Official page)
The Buffet Framework (Official page)
WP Basis (Official …