Use this query for wordpressmu users
“UPDATE wp_1_posts SET post_content = REPLACE(post_content, ‘www.test.com’, ‘www.secondtest.com’);”

Use this query for wordpress
“UPDATE wp_posts SET post_content = REPLACE(post_content, ‘www.test.com’, ‘www.secondtest.com’);”

Here is the list of files which are required in wordpress theme. Whenever you are creating the new theme for wordpress, make sure that following files are present in your theme.

style.css

The main stylesheet. This must be included with your Theme, and it must contain the information header for your Theme.

index.php

The main template. If your Theme provides its own templates, index.php must be present.

comments.php

The comments template. If not present, comments.php from the “default” Theme is used.

comments-popup.php

The popup comments template. If not present, comments-popup.php from the “default” Theme is used.

home.php

The home page template.

single.php

The single post template. Used when a single post is queried. For this and all other query templates, index.php is used if the query template is not present.

page.php

The page template. Used when an individual Page is queried.

category.php

The category template. Used when a category is queried.

tag.php

The tag template. Used when a tag is queried.

taxonomy.php

The term template. Used when a term in a custom taxonomy is queried.

author.php

The author template. Used when an author is queried.

date.php

The date/time template. Used when a date or time is queried. Year, month, day, hour, minute, second.

archive.php

The archive template. Used when a category, author, or date is queried. Note that this template will be overridden by category.php, author.php, and date.php for their respective query types.

search.php

The search results template. Used when a search is performed.

404.php

The 404 Not Found template. Used when WordPress cannot find a post or page that matches the query.

If you want show only some categories in wordpress menu than use following command in header.php.

<ul style=”float:left; width:840px;”>
<?php wp_list_categories(‘orderby=name&include=5,4,8,9,52,65,35′); ?>
</ul>

If you want exclude some categories in wordpress menu than use following command in header.php.

<ul style=”float:left; width:840px;”>
<?php wp_list_categories(‘orderby=name&exclude=5,4,8,9,52,65,35′); ?>
</ul>

Following Options we can use with “wp_list_categories” method.

<?php wp_list_categories( $args ); ?>

<?php $args = array(
'show_option_all' => ,
'orderby' => 'name',
'order' => 'ASC',
'show_last_update' => 0,
'style' => 'list',
'show_count' => 0,
'hide_empty' => 1,
'use_desc_for_title' => 1,
'child_of' => 0,
'feed' => ,
'feed_type' => ,
'feed_image' => ,
'exclude' => ,
'exclude_tree' => ,
'include' => ,
'current_category' => 0,
'hierarchical' => true,
'title_li' => __( 'Categories' ),
'number' => NULL,
'echo' => 1,
'depth' => 0 ); ?>

By default, the usage shows:

• No link to all categories
• Sorts the list of Categories by the Category name in ascending order
• Does not show the last update (last updated post in each Category)
• Displayed in an unordered list style
• Does not show the post count
• Displays only Categories with posts
• Sets the title attribute to the Category Description
• Is not restricted to the child_of any Category
• No feed or feed image used
• Does not exclude any Category and includes all Categories
• Displays the active Category with the CSS Class-Suffix ‘ current-cat’
• Shows the Categories in hierarchical indented fashion
• Display Category as the heading over the list
• No SQL LIMIT is imposed (‘number’ => 0 is not shown above)
• Displays (echos) the categories
• No limit to depth
• All categories.