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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 ...
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
...
Getting the object's property name
...
More specifically, Object.keys(obj) returns an array of property names, i.e. keys, belonging to the passed in obj.
– a learner has no name
Mar 26 '16 at 12:43
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Is it better to use std::memcpy() or std::copy() in terms to performance?
...y.
I wrote a C++ SHA-2 implementation. In my test, I hash 5 strings using all four SHA-2 versions (224, 256, 384, 512), and I loop 300 times. I measure times using Boost.timer. That 300 loop counter is enough to completely stabilize my results. I ran the test 5 times each, alternating between the m...
Only read selected columns
...g","Sep","Oct","Nov","Dec"))
dat <- fread("data.txt", drop = c(8:13))
All result in:
> data
Year Jan Feb Mar Apr May Jun
1 2009 -41 -27 -25 -31 -31 -39
2 2010 -41 -27 -25 -31 -31 -39
3 2011 -21 -27 -2 -6 -10 -32
UPDATE: When you don't want fread to return a data.table, use the data.ta...
How to check if activity is in foreground or in visible background?
... class. Good choices are your own implementation of the
Application or a Service (there are also a few variations of this
solution if you'd like to check activity visibility from the service).
Example
Implement custom Application class (note the isActivityVisible() static method):
publi...
How do you read CSS rule values with JavaScript?
I would like to return a string with all of the contents of a CSS rule, like the format you'd see in an inline style. I'd like to be able to do this without knowing what is contained in a particular rule, so I can't just pull them out by style name (like .style.width etc.)
...
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...
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
|...
Does SQLAlchemy have an equivalent of Django's get_or_create?
...
That's basically the way to do it, there is no shortcut readily available AFAIK.
You could generalize it ofcourse:
def get_or_create(session, model, defaults=None, **kwargs):
instance = session.query(model).filter_by(**kwargs).firs...