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Add new field to every document in a MongoDB collection
...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 example last 2 fields false, true specifies the upser...
How can I convert a datetime object to milliseconds since epoch (unix time) in Python?
... is a true unix timestamp as defined here en.wikipedia.org/wiki/Unix_time (and so will only be using the unix_time function from this answer) then you should wrap delta.total_seconds() with int to avoid ending up with a float
– corford
Dec 30 '14 at 11:20
...
Is String.Contains() faster than String.IndexOf()?
I have a string buffer of about 2000 characters and need to check the buffer if it contains a specific string.
Will do the check in a ASP.NET 2.0 webapp for every webrequest.
...
Load a UIView from nib in Swift
...
Original Solution
I created a XIB and a class named SomeView (used the same name for
convenience and readability). I based both on a UIView.
In the XIB, I changed the "File's Owner" class to SomeView (in the identity inspector).
I created a UIView outlet in S...
Is there a way to instantiate objects from a string holding their class name?
...<DerivedA>;
map["DerivedB"] = &createInstance<DerivedB>;
And then you can do
return map[some_string]();
Getting a new instance. Another idea is to have the types register themself:
// in base.hpp:
template<typename T> Base * createT() { return new T; }
struct BaseFactor...
See what has been installed via MacPorts
... postfix: "",
imageUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9....
Remove an item from a dictionary when its key is unknown
...re currently testing for object identity (is only returns True if both operands are represented by the same object in memory - this is not always the case with two object that compare equal with ==). If you are doing this on purpose, then you could rewrite your code as
some_dict = {key: value for k...
How to show vertical line to wrap the line in Vim?
... Note the highlight setting must be set after any colorscheme commands as that would override your highlight color.
– c4urself
Feb 15 '13 at 18:00
8
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Get DateTime.Now with milliseconds precision
...esolution of around 10-15 ms. See Eric Lippert's blog post about precision and accuracy for more details.
If you need more accurate timing than this, you may want to look into using an NTP client.
However, it's not clear that you really need millisecond accuracy here. If you don't care about the e...
How can I use grep to find a word inside a folder?
... a specific word occurs inside a directory containing many sub-directories and files. My searches for grep syntax shows I must specify the filename, i.e. grep string filename .
...