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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...
Delete all documents from index/type without deleting type
I know one can delete all documents from a certain type via deleteByQuery.
15 Answers
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How to remove k__BackingField from json when Deserialize
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Automatic Property syntax is actually not recommended if the class can be used in serialization. Reason being the backing field is generated by compiler which can be different each time code is compiled. This can cause incompatibility issues even if no chang...
How to check if the string is empty?
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s.strip() allocates a new string, which is pure waste. Use string.isspace()
– Clément
Jun 22 at 15:27
add a ...
Does reading an entire file leave the file handle open?
...hat on the particular Python implementation.
To understand what this is all about, pay particular attention to the actual file object. In your code, that object is mentioned only once, in an expression, and becomes inaccessible immediately after the read() call returns.
This means that the file...
error LNK2038: mismatch detected for '_ITERATOR_DEBUG_LEVEL': value '0' doesn't match value '2' in m
... of solutions to my problem but none helped. I tried clean, rebuild. Reinstalled visual 2010 and change from professional to ultimate. But still I dont know why I have this error.
My project look like this:
1 Exe Solution to test my static library.
1 Dll Solution static library.
Code which is conve...
Installing Google Protocol Buffers on mac
I would like to install the older version of Google Protocol Buffers (protobuf-2.4.1) on mac using Terminal command line. I tried with brew install protobuf , but the latest version 2.5.0 has been installed. Is it possible to install the older version from terminal.
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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...
Rename Files and Directories (Add Prefix)
I would like to add prefix on all folders and directories.
10 Answers
10
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Count the number occurrences of a character in a string
...e counts for a lot of the letters in a given string, Counter provides them all in a more succinct form. If you want the count for one letter from a lot of different strings, Counter provides no benefit.
– Brenden Brown
Feb 17 '15 at 19:30
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