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What is the difference between save and insert in Mongo DB?
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Save Vs Insert :
In your given examples, the behavior is essentially the same.
save behaves differently if it is passed with an "_id" parameter.
For save, If the document contains _id, it will upsert querying the collection on the _id field, If not, it will insert.
If a document does not...
Execution time of C program
I have a C program that aims to be run in parallel on several processors. I need to be able to record the execution time (which could be anywhere from 1 second to several minutes). I have searched for answers, but they all seem to suggest using the clock() function, which then involves calculating...
How to split a string literal across multiple lines in C / Objective-C?
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There are two ways to split strings over multiple lines:
Using \
All lines in C can be split into multiple lines using \.
Plain C:
char *my_string = "Line 1 \
Line 2";
Objective-C:
NSString *my_string = @"Line1 \
Line2";
Better approach
Th...
How to avoid explicit 'self' in Python?
...s leads to useful properties, such as: you can't add members which accidentally shadow non-members and thereby break code.
One extreme example: you can write a class without any knowledge of what base classes it might have, and always know whether you are accessing a member or not:
class A(some_fu...
What do *args and **kwargs mean? [duplicate]
...r **kwargs as the last items in your function definition’s argument list allows that function to accept an arbitrary number of arguments and/or keyword arguments.
For example, if you wanted to write a function that returned the sum of all its arguments, no matter how many you supply, you could wr...
How can I get the MAC and the IP address of a connected client in PHP?
... address, you could parse the output of netstat -ie in Linux, or ipconfig /all in Windows.
Client IP address
You can get the client IP from $_SERVER['REMOTE_ADDR']
Client MAC address
The client MAC address will not be available to you except in one special circumstance: if the client is on the s...
PHP “php://input” vs $_POST
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The reason is that php://input returns all the raw data after the HTTP-headers of the request, regardless of the content type.
The PHP superglobal $_POST, only is supposed to wrap data that is either
application/x-www-form-urlencoded (standard content type for...
Why aren't superclass __init__ methods automatically invoked?
...thon designers decide that subclasses' __init__() methods don't automatically call the __init__() methods of their superclasses, as in some other languages? Is the Pythonic and recommended idiom really like the following?
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What's the difference between SortedList and SortedDictionary?
...<TKey,TValue> ? Are there any circumstances where you would specifically use one and not the other?
7 Answers
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Input from the keyboard in command line application
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@PeterWebb - works fine in xcode terminal, falls through in playground :)
– aprofromindia
Apr 8 '16 at 14:50
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