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MongoDB relationships: embed or reference?
...irst consider what will make your queries easier. In many cases concern about document sizes will be premature optimization.
Complex data structures:
MongoDB can store arbitrary deep nested data structures, but cannot search them efficiently. If your data forms a tree, forest or graph, you effect...
Easiest way to convert int to string in C++
...do the originally macro-based type-agnostic solution (preserved below) without going through macro uglyness.
// variadic template
template < typename... Args >
std::string sstr( Args &&... args )
{
std::ostringstream sstr;
// fold expression
( sstr << std::dec <&l...
Variable declared in for-loop is local variable?
...ed to define a variable with the same name in both the for-loop as well as outside the for-loop is because variables in the outer-scope are valid in the inner-scope. Meaning that there would be two 'i' variables within the for-loop if this was allowed.
See: MSDN Scopes
Specifically:
The scope ...
How to use filter, map, and reduce in Python 3
...
You can read about the changes in What's New In Python 3.0. You should read it thoroughly when you move from 2.x to 3.x since a lot has been changed.
The whole answer here are quotes from the documentation.
Views And Iterators Instead Of Li...
What is CMake equivalent of 'configure --prefix=DIR && make all install '?
...&& make DESTDIR=/usr all install
Note that, as user7498341 points out, this is not appropriate for cases where you really should be using PREFIX.
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Can I use git diff on untracked files?
Is it possible to ask git diff to include untracked files in its diff output, or is my best bet to use git add on the newly created files and the existing files I have edited, then use:
...
Collections.emptyList() returns a List?
...));
}
Now when you're doing straight assignment, the compiler can figure out the generic type parameters for you. It's called type inference. For example, if you did this:
public Person(String name) {
List<String> emptyList = Collections.emptyList();
this(name, emptyList);
}
then th...
How can I list all foreign keys referencing a given table in SQL Server?
...:
EXEC sp_fkeys @pktable_name = 'TableName', @pktable_owner = 'dbo'
Without specifying the schema, the docs state the following:
If pktable_owner is not specified, the default table visibility rules
of the underlying DBMS apply.
In SQL Server, if the current user owns a table with the ...
Fast and responsive interactive charts/graphs: SVG, Canvas, other?
.... The current implementation, using Protovis, is underperformant. Check it out here:
5 Answers
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Converting from longitude\latitude to Cartesian coordinates
...es, WGS-84 assumes the Earth is an ellipsoid, but I believe you only get about a 0.5% average error using an approach like the "Haversine Formula", which may be an acceptable amount of error in your case. You will always have some amount of error unless you're talking about a distance of a few feet...