Internet site that has a very effective Query-by-Example (QBE) implementation

Internet site that has a very effective Query-by-Example (QBE) implementation

Identify an Internet site that has a very effective Query-by-Example (QBE) implementation for complex queries (multiple simultaneous attributes/fields) to efficiently navigate among the database (as described in the publisher's web site links to Chapters 2 and 9 of the 7th Edition of our text, http://wps.prenhall.com/bp_hoffer_mdm_8/0,12126,3390077-,00.html), QBE is more than just a single word/single phrase search capability found in some web site's so-called "advanced search" or one field product selection sites in that it is a Windows based query synthesis capability involving many of the database's attributes/fields simultaneously). Please re-read this to keep from selecting a search site that is not QBE by our definition (be careful in searching the web on this as there are a few bogus [erroneous] definitions of QBE out there - don't get confused on this). Provide the complete URL as a reference. Why is this QBE implementation so effective (what appeals to you about its use)?