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How to speed up insertion performance in PostgreSQL
...u've batched your work into big transactions, though.
INSERT or COPY in parallel from several connections. How many depends on your hardware's disk subsystem; as a rule of thumb, you want one connection per physical hard drive if using direct attached storage.
Set a high checkpoint_segments value an...
How to populate/instantiate a C# array with a single value?
I know that instantiated arrays of value types in C# are automatically populated with the default value of the type (e.g. false for bool, 0 for int, etc.).
...
Best practices for exception management in Java or C# [closed]
... to catch exceptions and turn them into error codes. Why do you think the caller would prefer error codes over exceptions when the latter is the default in both Java and C#?
As for your questions:
You should only catch exceptions that you can actually handle. Just
catching exceptions is not the ...
Java's Virtual Machine and CLR
As a sort of follow up to the question called Differences between MSIL and Java bytecode? , what is the (major) differences or similarity in how the Java Virtual Machine works versus how the .NET Framework Common Language Runtime (CLR) works?
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static function in C
... /* ok, f2 is in the same translation unit */
/* (basically same .c file) as f1 */
}
int f2(int foo) {
return 42 + foo;
}
main.c:
int f1(int); /* prototype */
int f2(int); /* prototype */
int main(void) {
f1(10); /* ok, f1 is visible to the linker */
f2(1...
Why are static variables considered evil?
...ate world. Recently I've developed an application using Groovy and Java. All through the code I wrote used quite a good number of statics. I was asked by the senior technical lot to cut down on the number of statics used. I've googled about the same, and I find that many programmers are fairly aga...
Does Qt support virtual pure slots?
My GUI project in Qt has a lot of "configuration pages" classes which all inherit directly from QWidget .
2 Answers
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Objective-C for Windows
...X so that any viable OS X program can run on Windows. Because GNUStep typically uses the latest version of gcc, they also add in support for Objective-C++ and a lot of the Objective-C 2.0 features.
I haven't tested those features with GNUStep, but if you use a sufficiently new version of gcc, you m...
What is a “Bitmap heap scan” in a query plan?
... stay in memory, but you get the point).
A bitmap index scan will sequentially open a short-list of disk pages, and grab every applicable row in each one (hence the so-called recheck cond you see in query plans).
Note, as an aside, how clustering/row order affects the associated costs with either ...
Limitations of Intel Assembly Syntax Compared to AT&T [closed]
...
There is really no advantage to one over the other. I agree though that Intel syntax is much easier to read. Keep in mind that, AFAIK, all GNU tools have the option to use Intel syntax also.
It looks like you can make GDB use Intel syn...