What's the difference between findAndModify and update in MongoDB?

Question

I\'m a little bit confused by the findAndModify method in MongoDB. What\'s the advantage of it over the update method? For me, it seems that it jus

Answer 1

One useful class of use cases is counters and similar cases. For example, take a look at this code (one of the MongoDB tests): find_and_modify4.js.

Thus, with findAndModify you increment the counter and get its incremented value in one step. Compare: if you (A) perform this operation in two steps and somebody else (B) does the same operation between your steps then A and B may get the same last counter value instead of two different (just one example of possible issues).