

Top 5 MongoDB gotchas - imslavko
http://devblog.me/wtf-mongo

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arkham
Just to clarify on positive/negative limits on a cursor: if the limit number
is negative, then the database will return that number of results and close
the cursor. No further results for that query can be fetched. If the limit is
positive you can leave the cursor open to receive further results, hence the
option for both. (see
[http://stackoverflow.com/a/11995057/1148648](http://stackoverflow.com/a/11995057/1148648))

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nasalgoat
So not only is performance abysmal, the query language has several non-obvious
syntax problems. In retrospect, the idea of using JSON as a query language
seems ill-advised and counter-intuitive.

I'm glad I am finally rid of MongoDB in my day-to-day job. I won't miss it.

~~~
imslavko
Well, those 5 are very specific corner cases. Most people will not face them
in real life.

~~~
nasalgoat
The array insert order syntax seems like something you'd encounter every day.

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BuzzKilla1960
Wouldn't the simpler, faster and more appropriate syntax be

if (N > 50 || N < 1) ??

~~~
BerislavLopac
No it wouldn't, because -30 is supposed to work the same as 30, so you want to
convert the sign to positive first. Personally, I'd use something like:

    
    
        if (!N || Math.abs(N) > 50 ) {
            N = 50
        };

