>But I also think that this feature should be implemented by a search >engine, so that it is easily accessible. Even if it is not >programmatically difficult to manually build the query, most beginners are >going to use the parser, and then ask the question why doesn't this >work. The prospect of building the query manually will sound difficult, >and may discourage them from using Lucene. > >So, if it can be implemented in such a way that you only take the >performance hit when you put the wildcard as the first letter, I would >like to see that implemented.
This is a sensible-sounding argument, but contains some hidden assumptions about your user base which can lead to very bad results in general. Lets call a LUCENE DEVELOPER someone who understands the internals of Lucene. (Such as me.) We'll call an APP DEVELOPER someone who uses Lucene to build an application. He understands the general issues involved in search and retrieval. (Such as you.) We'll call an APP USER someone who doesn't know anything about Java, Lucene, programming, or anything, but knows how to use Google. You are saying "I'm a savvy APP DEVELOPER, I know that certain search patterns are expensive, but why should I be precluded from using them? I'll be careful, and if I screw up, its my problem." That statement might be true if the universe of users of your app included only APP DEVELOPERS. But the query parser is explicitly designed for APP USERS. They don't know that certain classes of queries are much more expensive. They don't even know what "expensive" means in this context. So a user enters "*" into a search box, and it takes a really long time to run. Maybe they assume something got hung up somwhere, and they open _another_ browser window, and enter the same search. Now some random user has innocently created a DoS attack on your system. The Query Parser is a convenience for making common search options available to APP USERS. As such, it _must_ be designed with the assumption that the end user is an APP USER, not an APP DEVELOPER. Your users are smarter than this? Great! Build your queries with the query constructors. They're not hard to use. But just because your users are smart enough to use a chainsaw without cutting off their legs, doesn't mean that we should hand out chainsaws to APP USERS all over the world. -- Brian Goetz Quiotix Corporation [EMAIL PROTECTED] Tel: 650-843-1300 Fax: 650-324-8032 http://www.quiotix.com -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
