PHP MongoDB, update document without erasing the rest

Question

I'm trying to update a mongo document, using PHP and the update() function. However, when I do this, it replaces the WHOLE document with the value I wanted to update. How can I fix this?

The code I have written up to now: http://twaddlr.com/view/73 (Scroll down to the "update" function. It's a database wrapper I'm writting for my site)

Answer 1

The key is to use $set in the update, e.g. instead of this (sorry using JavaScript syntax here, not sure about the exact PHP driver syntax):

db.my_collection.update({hello: "world"}, {foo: "bar"})

you do

db.my_collection.update({hello: "world"}, {$set: {foo: "bar"}})

If you use $set, only the properties you specify will be updated, the whole document will not be replaced.

You can read more about this in the documentation, here: http://www.mongodb.org/display/DOCS/Updating#Updating-ModifierOperations

Edit: looking at your code, this is exactly what you do in the addRow method. Just do the same thing in update.