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SQL select join: is it possible to prefix all columns as 'prefix.*'?
...ee http://www.sqlite.org/pragma.html
Otherwise all I can recommend is to fetch columns in a result set by ordinal position rather than by column name, if it's too much trouble for you to type the names of the columns in your query.
This is a good example of why it's bad practice to use SELECT * --...
Understanding Canvas and Surface concepts
...u are familiar with that. All the logic on how to draw a circle, or a box, etc is contained inside Canvas. A canvas draws on a Bitmap or an open GL container but there is no reason why in the future it could be extended to draw onto other types of rasters.
SurfaceView is a View that contains a Surf...
How to create REST URLs without verbs?
...Don't use implementation-specific extensions in your URIs (.php, .py, .pl, etc.)
Don't fall into RPC with your URIs
Do limit your URI space as much as possible
Do keep path segments short
Do prefer either /resource or /resource/; create 301 redirects from the one you don't use
Do use query parameter...
Link to all Visual Studio $ variables
I was having a look at $(Configuration) , $(ProjectDir) etc. in Visual Studio 2008 for Prebuild events.
7 Answers
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What's Pros and Cons: putting javascript in head and putting just before the body close
...er the page is visible to the user.
If you are adding styles or elements (etc. switching textfields with some form of richer editor) this will be visible to the user as flickering.
If you are adding click-events to elements, they will not be clickable until a bit after the elements themselves are ...
How does C compute sin() and other math functions?
...at book, you can decide if you have a hardware adder, multiplier, divider, etc, and decide which operations are fastest. e.g. If you had a really fast divider, the fastest way to calculate sine might be P1(x)/P2(x) where P1, P2 are Chebyshev polynomials. Without the fast divider, it might be just P(...
Performance difference for control structures 'for' and 'foreach' in C#
...get:
list[0]; // head
list[1]; // head.Next
list[2]; // head.Next.Next
// etc.
When you call GetEnumerator (implicitly using the forach-syntax), you'll get an IEnumerator object that has a pointer to the head node. Each time you call MoveNext, that pointer is moved to the next node, like so:
IEn...
JPA: How to have one-to-many relation of the same Entity type
... Collection<A> children;
// Getters, Setters, serialVersionUID, etc...
}
Here's a rough main() method that persists three such entities:
public static void main(String[] args) {
EntityManager em = ... // from EntityManagerFactory, injection, etc.
em.getTransaction().begin();
...
Is it good practice to make the constructor throw an exception? [duplicate]
... recover. Ex. An object constructor loads test data (usernames, passwords, etc.) from a config file. All tests then use the data in config object. Exceptions can be thrown if the file can't be found, data is in wrong format etc. I think the only way we can recover from the exceptions is by making a ...
How do I use valgrind to find memory leaks?
...all Valgrind on your system.
sudo apt install valgrind # Ubuntu, Debian, etc.
sudo yum install valgrind # RHEL, CentOS, Fedora, etc.
Valgrind is readily usable for C/C++ code, but can even be used for other
languages when configured properly (see this for Python).
To run Valgrind, pass the ex...