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Oracle Differences between NVL and Coalesce
...you can find a difference in the fact that NVL makes an implicit data type casting if the given values are of different types. So for instance, I was getting an error using COALESCE passing it two NULL values (one explicitly set and the other taken from a column in the database, of type NUMBER), tha...
How do I get a distinct, ordered list of names from a DataTable using LINQ?
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Try out the following:
dataTable.Rows.Cast<DataRow>().select(dr => dr["Name"].ToString()).Distinct().OrderBy(name => name);
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Why does Android use Java? [closed]
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Some points:
Java is a known language, developers know it and don't have to learn it
it's harder to shoot yourself with Java than with C/C++ code since it has no pointer arithmetic
it runs in a VM, so no need to recompile it for every phone out there and easy to secure
large number ...
How do I find the location of Python module sources?
...king at themodule.__file__.
The datetime module, however, is written in C, and therefore datetime.__file__ points to a .so file (there is no datetime.__file__ on Windows), and therefore, you can't see the source.
If you download a python source tarball and extract it, the modules' code can be found...
VBoxManage: error: Failed to create the host-only adapter
I am running vagrant 1.4 and virtual box 4.3 on fedora 17 machine. When I do "vagrant up", I get this error:
32 Answers...
How to repeat a string a variable number of times in C++?
... @Brent The OP asked for both - "'n' spaces (or any string)", and then goes on to demonstrate their intent with a single period as the string. English is not many people's first language so you sometimes need to guess their exact requirements and when analysed, the question is really as...
Java - Method name collision in interface implementation
...Something2 ) are expected ? I cannot even expect client code to be able to cast my instance to the appropriate interface , so am I not loosing something by this restriction ? Also note that in this way , when writing classes that actually implement the respective interfaces , we loose the benefit of...
How can I pass a member function where a free function is expected?
...n using a void* interface as they remove the potential for errors due to a cast to the wrong type.
To clarify how to use a function pointer to call a member function, here is an example:
// the function using the function pointers:
void somefunction(void (*fptr)(void*, int, int), void* context) {
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What is the difference between string primitives and String objects in JavaScript?
...(s).prototype.toString.call = [object String].
The auto-boxing behaviour casts s back and forth to its wrapper type as needed, but the standard operations are incredibly fast since you are dealing with a simpler data type. However auto-boxing and Object.prototype.valueOf have different effects.
I...
When you exit a C application, is the malloc-ed memory automatically freed?
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It depends on the operating system. The majority of modern (and all major) operating systems will free memory not freed by the program when it ends.
Relying on this is bad practice and it is better to free it explicitly. The issue isn't just that your code looks bad. You may decide y...