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Select first row in each GROUP BY group?
... Informix 12.x also supports window functions (the CTE needs to be converted to a derived table though). And Firebird 3.0 will also support Window functions
– a_horse_with_no_name
Mar 14 '14 at 9:19
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How to upload files to server using JSP/Servlet?
...servlet application
How to upload an image and save it in database?
How to convert Part to Blob, so I can store it in MySQL?
Serving uploaded file
Head to the following answers for detail on properly serving the saved file from disk or database back to the client:
Load images from outside of we...
std::function and std::bind: what are they, and when should they be used?
...to bind the three parameters you can do like this
// a template class for converting a member function of the type int function(int,int,int)
//to be called as a function object
template<typename _Ret,typename _Class,typename _arg1,typename _arg2,typename _arg3>
class mem_fun3_t
{
public:
...
What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
...e queries are really fast, but it's the round trips that wreak havok. I've converted "WHERE Id = const" to "WHERE Id IN (const, const, ...)" and gotten orders of magnitude increases out of it.
– Hans
Oct 2 '12 at 23:07
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When to use the brace-enclosed initializer?
...no constructor taking std::initializer_list interfering. Similarly std::is_convertible is of no help.
I've investigated if it is in fact possible to hand-roll a trait that can fix that but I'm not overly optimistic about that. In any case I don't think we would be missing much, I think that the fac...
Difference between Big-O and Little-O Notation
...it still has a lim sup: 4.)
I recommend memorizing how the Big-O notation converts to asymptotic comparisons. The comparisons are easier to remember, but less flexible because you can't say things like nO(1) = P.
share
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How to read a (static) file from inside a Python package?
...s the path separator, even if you are on Windows. Setuptools automatically converts slashes to appropriate platform-specific separators at build time
In case you wonder where the documentation is:
PEP 0365
https://packaging.python.org/guides/single-sourcing-package-version/
...
What do
...icit parameter of type A =:= String you're saying that A can be implicitly converted to String. If you changed the order and made the implicit argument be of type String =:= A, it wouldn't work, because this would be an implicit conversion from String to A.
– Tom Crockett
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GridLayout and Row/Column Span Woe
...id Support package, the layout breaks" -- actually, that was my fault, not converting the required android: attributes to app: ones, using the backport's XML namespace. It does work with the backport.
– CommonsWare
Aug 8 '12 at 23:44
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What is the difference between “JPG” / “JPEG” / “PNG” / “BMP” / “GIF” / “TIFF” Image?
...pha Transparency for PNG-8 files. (Damn you, Photoshop!) There are ways to convert Photoshop PNG-24 to PNG-8 files while retaining their transparency, though. One method is PNGQuant, another is to save your files with Fireworks.
PNG-24 - Lossless / Direct
PNG-24 is a great format that combines L...