Hello,

I am trying to add the ability to use sub categories to my database and I need help with a query. My design:

Code:
CREATE TABLE `Articles` (
  `ID` int(11) unsigned NOT NULL auto_increment,
  `Name` text NOT NULL,
  `Body` longtext NOT NULL,
  `Date` datetime NOT NULL default '0000-00-00 00:00:00',
  `Picture` varchar(100) default NULL,
  `Description` text NOT NULL
  PRIMARY KEY  (`ID`),
)

CREATE TABLE `Categories` (
  `ID` int(11) unsigned NOT NULL auto_increment,
  `ParentID` int(11) unsigned NOT NULL default '0',
  `Name` varchar(100) NOT NULL default ''
  PRIMARY KEY  (`ID`),
  UNIQUE KEY `Name` (`Name`)
)

CREATE TABLE `CatLookup` (
  `ArticleID` int(11) unsigned NOT NULL default '0',
  `CatID` int(11) unsigned NOT NULL default '0',
  PRIMARY KEY  (`ArticleID`,`CatID`),
  KEY `CatID` (`CatID`)
)
What I would like to do, is pull out all the articles that are for a particular category, and ALL articles in ALL sub categories for that category. I am having trouble with the SQL. I know how to get the articles from one particular category (a la WHERE CatID = 3 ...), but I am having trouble translating that into many categories. I think I need to somehow get the ID's of the children, then pass them into the WHERE clause (WHERE CatID = 3, 4, 5, 6, etc...), but I'm not familiar with how this would be done. Any ideas?

Ben