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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 docu...
filter items in a python dictionary where keys contain a specific string
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How about a dict comprehension:
filtered_dict = {k:v for k,v in d.iteritems() if filter_string in k}
One you see it, it should be self-explanatory, as it reads like English pretty well.
This syntax requires Python 2.7 or greater.
In Python 3, there is only dict.items(), not ...
What does void mean in C, C++, and C#?
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Basically it means "nothing" or "no type"
There are 3 basic ways that void is used:
Function argument: int myFunc(void)
-- the function takes nothing.
Function return value: void myFunc(int)
-- the function returns nothing
Generic data pointer: void*...
How do I lowercase a string in Python?
Is there a way to convert a string from uppercase, or even part uppercase to lowercase?
5 Answers
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Are Roslyn SyntaxNodes reused?
...PDATE: This question was the subject of my blog on June 8th, 2012. Thanks for the great question!
Great question. We debated the issues you raise for a long, long time.
We would like to have a data structure that has the following characteristics:
Immutable.
The form of a tree.
Cheap access to...
Can I safely delete contents of Xcode Derived data folder?
...y that among other things that ~/Library/Developer/Xcode/DerivedData directory is taking about 22GB of disk space.
13 Answe...
Implementing Fast and Efficient Core Data Import on iOS 5
...it until the end to save. It has its own thread, and it will help keep memory down as well.
You wrote:
Then at the end of the import process, I save on the master/parent
context which, ostensibly, pushes modifications out to the other child
contexts including the main context:
In your co...
Catch-22 prevents streamed TCP WCF service securable by WIF; ruining my Christmas, mental health
...m looking at you, MTOM1) due to a fundamental issue in how it fails to perform preauthentication the way most people would think that should work (it only affects subsequent requests for that channel, not the first request) Ok, so this is not exactly your issue but please follow along as I will get ...
How to change the value of attribute in appSettings section with Web.config transformation
Is it possible to transform the following Web.config appSettings file:
4 Answers
4
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How does the vim “write with sudo” trick work?
...t allows you to write on a file that needs root permission, even when you forgot to open vim with sudo:
8 Answers
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