My boss wants me to make a version of our company's web app that allows a guest user to look around inside the system to see the product features.

Would it be possible to set up a duplicate database to in Postgresql so you cannot really save changes? I would like to have it so I do not have to reprogram anything, the database will accept commands like add and update but it would just be unable to actually save them- the changes would just go nowhere.

Possible?

Gosh, don't know. Somone else may.

You could restore a snapshot of the production database every X number of hours or once a day or something and get it back that way. Just a thought.

Anyone? I need help here- if a knowledgeable person thinks this is impossible, please let me know and I will go with my plan B idea, static HTML output captures of my web application.

I don't know how big or complex your database is, but maybe you can make temporary copies of the database, or a scaled-down version of it, for use by the web app. I just tried using postgresql's creatdb command to make a copy of a database containing 16 tables each having about 5000 - 10000 rows of 4 to 12 columns. It took 4 seconds on a 2 GHz P4, which might be acceptable on a web server that is not too heavily loaded. The temporary databases could be pruned on a scheduled basis, or tied to your web app's session management system for deletion, or both. Just a thought.

--- rod.

I implemented this solution by adding an IF clause in PHP to the part of my script that actually processed the SQL query, if the $_SESSION['demo'] variable is set to TRUE, then the query does not run.

Somewhat inelegant, since I had to add this clause to three seperate pages, but still it works fine. Good thing I run all my regular queries through one function!