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    <p>You need to set your table up for a recursive one-to-many relationship, like this making a few assumptions about data types):</p> <pre><code>CREATE TABLE [Categories] ( CategoryID int NOT NULL PRIMARY KEY, CategoryName varchar(255) NOT NULL, ParentCategoryID int NULL, -- Level field is not needed; can be dynamically determined CONSTRAINT FK_Child_to_Parent FOREIGN KEY (ParentCategoryID) REFERENCES [Categories] (CategoryID) ) </code></pre> <p>In order to query this table in general, you need to use a self-join, like this (note the from/join; this is the part you will re-use):</p> <pre><code>select child.*, parent.* from Categories child join Categories parent on child.ParentCategoryID = parent.CategoryID </code></pre> <p>You can tell when you are looking at a parent category because the value for <code>ParentCategoryID</code> will be <code>NULL</code>. To answer your question of how to get child categories for your page given a parent ID, you can use this:</p> <pre><code>select child.CategoryID, child.CategoryName from Categories child join Categories parent on child.ParentCategoryID = parent.CategoryID where parent.ParentCategoryID = [some value] </code></pre> <p>There are tons of tutorials/designs out there if you Google "recursive database table" or related terms; for starters, here is one (picked at random):<a href="http://www.tomjewett.com/dbdesign/dbdesign.php?page=recursive.php" rel="nofollow">http://www.tomjewett.com/dbdesign/dbdesign.php?page=recursive.php</a></p>
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    1. COI don't know .net 4.0 well just learning but what I want to accomplish is url routing with multiple categories in the url eg. www.something.com/clothing/mens/somepage.aspx the hard part to all this is managing it on the adminstration side. I'd need to have an insert textbox with a listbox and form next to it to update the selected Item and with the selected item create another select box of sub categories.
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Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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