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Difference between a Structure and a Union
...good example to give the difference between a struct and a union ?
Basically I know that struct uses all the memory of its member and union uses the largest members memory space. Is there any other OS level difference?
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How to find duplicates in 2 columns not 1
I have a MySQL database table with two columns that interest me. Individually they can each have duplicates, but they should never have a duplicate of BOTH of them having the same value.
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What does the construct x = x || y mean?
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It means the title argument is optional. So if you call the method with no arguments it will use a default value of "Error".
It's shorthand for writing:
if (!title) {
title = "Error";
}
This kind of shorthand trick with boolean expressions is common in Perl too. With the...
C++ performance vs. Java/C#
...p of a virtual machine which abstracts away the native architecture. Logically it would seem impossible for Java or C# to match the speed of C++ because of this intermediate step, however I've been told that the latest compilers ("hot spot") can attain this speed or even exceed it.
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Browsers' default CSS for HTML elements
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A GitHub repository of all W3C HTML spec and vendor default CSS stylesheets can be found here
1. Default Styles for Firefox
2. Default Styles for Internet Explorer
3. Default Styles for Chrome / Webkit
4. Default Styles for Opera
5. Default St...
What is Normalisation (or Normalization)?
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Normalization is basically to design a database schema such that duplicate and redundant data is avoided. If some piece of data is duplicated several places in the database, there is the risk that it is updated in one place but not the other, lead...
Meaning of acronym SSO in the context of std::string
... variables ("from the stack", which are variables that you create without calling malloc / new) are generally much faster than those involving the free store ("the heap", which are variables that are created using new). However, the size of automatic arrays is fixed at compile time, but the size of ...
Calculate last day of month in JavaScript
...fectly well. Out of curiosity, what are you using to run the javascript on all these engines? Got everything set-up or some kind of tool?
– neonski
Oct 21 '08 at 17:04
5
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Storing money in a decimal column - what precision and scale?
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If you are looking for a one-size-fits-all, I'd suggest DECIMAL(19, 4) is a popular choice (a quick Google bears this out). I think this originates from the old VBA/Access/Jet Currency data type, being the first fixed point decimal type in the language; Decimal on...
C# Object Pooling Pattern implementation
...ctPool type, which is used to pool frequently used objects which would normally get new'ed up and garbage collected very often. This reduces the amount and size of garbage collection operations which have to happen. There are a few different sub-implementations all using ObjectPool (See: Why are the...