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Add new field to every document in a MongoDB collection
...field" : 1, "test" : "a" }
EDIT:
In case you want to add a new_field to all your collection, you have to use empty selector, and set multi flag to true (last param) to update all the documents
db.your_collection.update(
{},
{ $set: {"new_field": 1} },
false,
true
)
EDIT:
In the above ...
How to get disk capacity and free space of remote computer
...20 vs. 10^6. It should indeed be written 1MiB (with proper case) but is usually shown in lower case, without th "i". See Mebibyte.
– Matthieu
Mar 3 at 12:09
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How much is the overhead of smart pointers compared to normal pointers in C++?
..._ptr always has memory overhead for reference counter, though it is very small.
std::unique_ptr has time overhead only during constructor (if it has to copy the provided deleter and/or null-initialize the pointer) and during destructor (to destroy the owned object).
std::shared_ptr has time overhe...
What characters are allowed in DOM IDs? [duplicate]
...
Actually there is a difference between HTML and XHTML.
As XHTML is XML the rules for XML IDs apply:
Values of type ID MUST match the Name production.
NameStartChar ::= ":" | [A-Z] | "_" | [a-z] | [#xC0-#xD6] |
...
Using a piano keyboard as a computer keyboard [closed]
I have RSI problems and have tried 30 different computer keyboards which all caused me pain. Playing piano does not cause me pain. I have played piano for around 20 years without any pain issues. I would like to know if there is a way to capture MIDI from a MIDI keyboard and output keyboard stroke...
WKWebView not loading local files under iOS 8
...
They finally solved the bug! Now we can use -[WKWebView loadFileURL:allowingReadAccessToURL:].
Apparently the fix was worth some seconds in WWDC 2015 video 504 Introducing Safari View Controller
For iOS8 ~ iOS10 (Swift 3)
As Da...
Bash function to find newest file matching pattern
... Your one liner is giving me right answer, but the "right" way is actually giving me the oldest file. Any idea why?
– NewNameStat
Apr 4 '19 at 21:59
|...
python pandas remove duplicate columns
...he given example, the returned value would be [False,False,True].
Pandas allows one to index using boolean values whereby it selects only the True values. Since we want to keep the unduplicated columns, we need the above boolean array to be flipped (ie [True, True, False] = ~[False,False,True])
F...
GoogleTest: How to skip a test?
...o). I then removed my comment, figuring it's obsolete... but that's some really good info! +1
– Kiril
Aug 26 '11 at 17:05
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Double vs. BigDecimal?
...tudes (say d1=1000.0 and d2=0.001) could result in the 0.001 being dropped alltogether when summing as the difference in magnitude is so large. With BigDecimal this would not happen.
The disadvantage of BigDecimal is that it's slower, and it's a bit more difficult to program algorithms that way (du...