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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...
AttributeError: 'module' object has no attribute 'tests'
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I finally figured it out working on another problem. The problem was that my test couldn't find an import.
It looks like you get the above error if your test fails to import. This makes sense because the test suite can't import ...
Passing argument to alias in bash [duplicate]
...etom: If you're referring to the colors in my answer, that's done automatically by the syntax highlighter.
– Paused until further notice.
Jul 7 '14 at 5:12
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Can I zip more than two lists together in Scala?
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Scala treats all of its different tuple sizes as different classes (Tuple1, Tuple2, Tuple3, Tuple4,...,Tuple22) while they do all inherit from the Product trait, that trait doesn't carry enough information to actually use the data values ...
fs: how do I locate a parent folder?
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why? just generally why? can someone please explain?
– eyurdakul
May 16 '17 at 15:12
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How to replace a hash key with another key
...n't like "smart" ruby code because it takes some time to tell what it is really doing. Your solution is in other hand simple and descriptive.
– Lucas
Nov 13 '14 at 18:55
3
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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...
Understanding Python super() with __init__() methods [duplicate]
...can be nice. But the main advantage comes with multiple inheritance, where all sorts of fun stuff can happen. See the standard docs on super if you haven't already.
Note that the syntax changed in Python 3.0: you can just say super().__init__() instead of super(ChildB, self).__init__() which IMO is...
Bash continuation lines
... like a single string which crosses lines, while indenting but not getting all those spaces, one approach you can try is to ditch the continuation line and use variables:
$ a="continuation"
$ b="lines"
$ echo $a$b
continuationlines
This will allow you to have cleanly indented code at the expense ...
Multiple variables in a 'with' statement?
...textlib.nested, this guarantees that a and b will have their __exit__()'s called even if C() or it's __enter__() method raises an exception.
You can also use earlier variables in later definitions (h/t Ahmad below):
with A() as a, B(a) as b, C(a, b) as c:
doSomething(a, c)
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