Question

I have a database for an E-commerce storefront. MSSQL 2008.

I have a table called Products and a table called Tags. This is a many to many relationship that is bound together by a table called ProductTags.

Products:
id, name, price

Tags:
id, name, sortorder, parentid(allow nulls)

ProductTags:
productid, tagid

I’m trying to create a View in SQL, but I just completely suck at writing SQL.

The View should consist of:
Tags.id, Tags.Name, Tags.sortorder, Tags.parentid, ProductCount, ChildTagCount

ProductCount is the number of products associated to this Tag. ChildTagCount is the number of Tags that has this Tag’s id as its parentid.

Answer 1

SELECT Tags.ID, Tags.Name, Tags.SortOrder, Tags.ParentID,        COUNT(DISTINCT ProductTags.ProductID) AS ProductCount,         COUNT(DISTINCT ChildTags.ID) AS ChildTagCount FROM Tags LEFT OUTER JOIN ProductTags ON Tags.ID = ProductTags.TagID LEFT OUTER JOIN Tags ChildTags ON Tags.ID = ChildTags.ParentID GROUP BY Tags.ID, Tags.Name, Tags.SortOrder, Tags.ParentID