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MongoDB Aggregation: How to get total records count?
... is one of the most commonly asked question to obtain the paginated result and the total number of results simultaneously in single query. I can't explain how I felt when I finally achieved it LOL.
$result = $collection->aggregate(array(
array('$match' => $document),
array('$group' => ...
One line if-condition-assignment
...ssible in Python, since what you're actually trying to do probably gets expanded to something like this:
num1 = 20 if someBoolValue else num1
If you exclude else num1, you'll receive a syntax error since I'm quite sure that the assignment must actually return something.
As others have already me...
How to compare binary files to check if they are the same?
What is the easiest way (using a graphical tool or command line on Ubuntu Linux) to know if two binary files are the same or not (except for the time stamps)? I do not need to actually extract the difference. I just need to know whether they are the same or not.
...
How to remove first 10 characters from a string?
...
And for better readability, you can use "". It compiles exactly the same as string.Empty these days.
– PRMan
Oct 15 '19 at 20:46
...
How do you find out the caller function in JavaScript?
... alert("caller is " + Hello.caller);
}
Note that this feature is non-standard, from Function.caller:
Non-standard
This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompa...
Add primary key to existing table
...
drop constraint and recreate it
alter table Persion drop CONSTRAINT <constraint_name>
alter table Persion add primary key (persionId,Pname,PMID)
edit:
you can find the constraint name by using the query below:
select OBJECT_NAME(...
Why do stacks typically grow downwards?
...the matter are that early CPUs got their original program counter set to 0 and it was a natural desire to start the stack at the other end and grow downwards, since their code naturally grows upward.
As an aside, note that this setting of the program counter to 0 on reset is not the case for all...
How to produce a range with step n in bash? (generate a sequence of numbers with increments)
...rd a guess that the downvote was due to your answer being generic to 'sh', and not specific to 'bash'. The pure Bash approach {begin end step} performs just a little better.The older 'seq' method's handy on older or smaller-memory systems like busybox. I did upvote both your and TheBonsai's answ...
How to declare a global variable in php?
...T is attempted to modify? Is it just like final in Java or const in C, C++ and C#?
– Lion
Nov 23 '12 at 14:05
...
Measuring code execution time
...ferences.
Stopwatch Class - Microsoft Docs
Provides a set of methods and properties that you can use to
accurately measure elapsed time.
Stopwatch stopwatch = Stopwatch.StartNew(); //creates and start the instance of Stopwatch
//your sample code
System.Threading.Thread.Sleep(500);
stopwatc...