Although I recommend you always put as much of your content into databases as possible, I do not suggest you rely on user queries to generate most of your web content. That can be SEO death, since the search engines do not submit queries, they just follow links.

Sometimes, however, you need to have some part of your website generate pages in response to user queries. You may have a large database that you do not want to allow scrapers to scarf up in its entirety, for example. So you design a query that allows users to view parts of the data, in response to their query, but limiting the output to a fixed number of responses, or else limit wild-card use in the queries, so they can’t get everything.

Basically, all of the database is available, but you would need to know exactly what is in it, in order to retrieve all of the content. Well if the scrapers knew everything in the database before-hand they wouldn’t need to scrape it. So in practice, you are protecting the integrity of your database without restricting clients from seeking specific data. They just can’t browse through all of the information.

But how, then, do you make this information available for the search engines? Well, as stated above, search engines follow links, so give them links. Put a list of ‘recent searches’ on your search page, and you turn a ‘content-less’ form page into a valuable links page. Of course you link each search term to the search engine so that clicking it will give the search results for that term, using a GET query format, so the search term goes in the URL.

The search engines follow those links, and now you have additional pages added gradually and naturally to the search engine index, making it look like the site is continually growing — always a good sign to search engines. When search terms ‘fall off’ the list, the search engines hardly notice — the results page is in their index, and shows up when they re-visit, so they don’t remove it from the index.