Question

Each record in the collection has two key “ip” and “timestamp”

db.posts.update({'ip' : '127.0.0.1', 'timestamp' : {'$gt' : sometimestamp}}, {'$set' : {'timestamp' : time.time()}, True)

The command above will insert a new record, if field “ip” with “127.0.0.1” not in the collection or “timestamp” is less than sometimestamp

Now, if I want to insert a new record only “ip” with “127.0.0.1” not in collection, in other word, keep value of “ip” unique.

How to do ?

Answer 1

What you are probably trying to do is this:

if( ip=127)
   if( ts > myts)
      update;
    else
      DO NOTHING;
else
   insert;

So essentially, you are having two different types of updates..One is going to acutally make a change in timestamp and other tells mongo to do nothing, i.e., not even make an insert.
I am guessing this is not possible with an upsert. So better use simple updates as follows:

db.posts.update ( { 'ip' : '127.0.0.1', 'timestamp' : { '$gt' : sometimestamp } } , { '$set' : { 'timestamp' : time.time() } , False)

And I don’t know how you’d write it in Pymongo, but logically speaking, you do this:

if (db.posts.find_one( { 'ip':'127.0.0.1'} ) != null):
    db.posts.update ( {'ip' : '127.0.0.1'}, { '$set' : {'timestamp' : time.time() } } )

Unfortunately, I can’t comment on the performance..