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Does MongoDB's $in clause guarantee order
...d index order as shown.
If you need to preserve this order, then you basically have two options.
So let's say that you were matching on the values of _id in your documents with an array that is going to be passed in to the $in as [ 4, 2, 8 ].
Approach using Aggregate
var list = [ 4, 2, 8 ];
...
Why does pthread_cond_wait have spurious wakeups?
...sor systems, making condition wakeup completely predictable might substantially slow all condition variable operations.
In the following comp.programming.threads discussion, he expands on the thinking behind the design:
Patrick Doyle wrote:
> In article , Tom Payne wrote:
> >Kaz Kyl...
How to change package name of Android Project in Eclipse?
...ckbox because by making "check" to this check-box, it will make changes to all the references of the package which are referred by other components of project.
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Do DOM tree elements with ids become global variables?
...ts’ are added as apparent properties of the document object. This is a really bad idea, as it allows element names to clash with real properties of document.
IE made the situation worse by also adding named elements as properties of the window object. This is doubly bad in that now you have to av...
What is the difference between tree depth and height?
... node" it is not correct , the leaf must be the one which is deepest among all the leaves of the given node.
– mightyWOZ
Jul 14 '16 at 7:53
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Remove characters after specific character in string, then remove substring?
...t I couldn't find quite what I needed (except in another language: Remove All Text After Certain Point ).
8 Answers
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What are the differences between type() and isinstance()?
...identity of types and rejects instances of subtypes, AKA subclasses).
Normally, in Python, you want your code to support inheritance, of course (since inheritance is so handy, it would be bad to stop code using yours from using it!), so isinstance is less bad than checking identity of types because...
Why shouldn't I use mysql_* functions in PHP?
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The MySQL extension:
Is not under active development
Is officially deprecated as of PHP 5.5 (released June 2013).
Has been removed entirely as of PHP 7.0 (released December 2015)
This means that as of 31 Dec 2018 it does not exist in any supported version of PHP. If you are using a ve...
Can a constructor in Java be private?
...ou can have one constructor that takes lots of different options that is really an implementation detail, so you make it private, but then your remaining constructors delegate to it.
As an example of delegating constructors, the following class allows you to save a value and a type, but it only let...
Is REST DELETE really idempotent?
...ce refers to the state of the system after the request has completed
In all cases (apart from the error issues - see below), the account no longer exists.
From here
"Methods can also have the property of
"idempotence" in that (aside from
error or expiration issues) the
side-effects of...
