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Foreign keys in mongo?
...Mongoid::Document
field :name
has_many :scores
end
Edit:
> db.foo.insert({group:"phones"})
> db.foo.find()
{ "_id" : ObjectId("4df6539ae90592692ccc9940"), "group" : "phones" }
{ "_id" : ObjectId("4df6540fe90592692ccc9941"), "group" : "phones" }
>db.foo.find({'_id...
Creating C formatted strings (not printing them)
...ee snprintf for a safer version).
A terminating null character is automatically appended after the
content.
After the format parameter, the function expects at least as many
additional arguments as needed for format.
Parameters:
str
Pointer to a buffer where the resulting C-string is stored. The ...
add column to mysql table if it does not exist
...
OK this is really crude but someone's got to say it. if you are simply running a SQL script from the command line, you can give mysql the --force switch, which means keep going even if there's an error. then, just go for it. you just want...
The key must be an application-specific resource id
...
That's the best way to get unique tag id ? Really Android ?
– jimmy0251
Mar 13 '15 at 10:24
...
How do you build a Singleton in Dart?
... There's the weird syntax Singleton._internal(); that looks like a method call when it's really a constructor definition. There's the _internal name. And there's the nifty language design point that Dart lets you start out (dart out?) using an ordinary constructor and then, if needed, change it to a...
How do I sort a vector of pairs based on the second element of the pair?
...response to your edits to your question, here's some thoughts ...
if you really wanna be creative and be able to reuse this concept a lot, just make a template:
template <class T1, class T2, class Pred = std::less<T2> >
struct sort_pair_second {
bool operator()(const std::pair<T1...
Why does changing the returned variable in a finally block not change the return value?
...atement executes is the value returned by the method. The fact that the finally clause later changes the value of s (after the return statement completes) does not (at that point) change the return value.
Note that the above deals with changes to the value of s itself in the finally block, not to th...
Iterating over all the keys of a map
Is there a way to get a list of all the keys in a Go language map? The number of elements is given by len() , but if I have a map like:
...
How to unpack and pack pkg file?
I have a pkg file created by Install Maker for Mac.
I want to replace one file in pkg. But I must do this under Linux system, because this is a part of download process. When user starts to download file server must replace one file in pkg.
I have a solution how unpack pkg and replace a file but I d...
Can a C# class inherit attributes from its interface?
...h is searched for the attributes.</param>
/// <returns>Returns all attributes.</returns>
public static T[] GetCustomAttributes<T>( this Type type ) where T : Attribute
{
return GetCustomAttributes( type, typeof( T ), false ).Select( arg => (T)arg ).ToArray();
}
/// <...