Why should I bother with unit testing if I can just use integration tests?

Question

Ok, I know I am going out on a limb making a statement like that, so my question is for everyone to convince me I am wrong. Take this scenario:

I have method A, which ca

Answer 1

If A is a query that runs for 2 hours, and prepares data for B, which is another query that runs for 2 hours, why should I wait 4 hours to find a problem when I could wait 2? It's not like this is a new idea. Do you think car companies assemble the entire car before seeing if the engine works?