I do this fairly often, but after talking to some other people I realized it might be a good idea to share a couple of quick SQL scripts. The idea is: you have some large operations you are doing on your database. Of the kind where you load or update lots of data – which means that it will run a lot faster with the constraints in the database turned off. All of them, or maybe just the FOREIGN KEYs, depending on exactly what you are doing. The following simple queries will generate SQL scripts that drop all your constraints, and then re-create them. Adding filters for just a single table/namespace/constrainttype is trivial, but left as an exercise for the reader…

Mas:

http://blog.hagander.net/archives/131-Automatically-dropping-and-creating-constraints.html