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How to select the nth row in a SQL database table?
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There are ways of doing this in optional parts of the standard, but a lot of databases support their own way of doing it.
A really good site that talks about this and other things is http://troels.arvin.dk/db/rdbms/#select-limit.
Basically, PostgreSQL and MySQL supports the non-...
Is 'switch' faster than 'if'?
...ntly increase performance in some scenarios, is as general as a switch is, and does not result in greater generated code size. But to see that, your test code would need a LOT more branches to see any difference.
To answer your specific questions:
Clang generates one that looks like this:
test_s...
(this == null) in C#!
...spec (section 7.5.7), you shouldn't be able to access this in that context and the ability to do so in C# 3.0 compiler is a bug. C# 4.0 compiler is behaving correctly according to the spec (even in Beta 1, this is a compile time error):
§ 7.5.7 This access
A this-access consists of the res...
Event system in Python
...raries to choose from, using very different terminology (events, signals, handlers, method dispatch, hooks, ...).
I'm trying to keep an overview of the above packages, plus the techniques mentioned in the answers here.
First, some terminology...
Observer pattern
The most basic style of event system ...
How to remove the first and the last character of a string
I'm wondering how to remove the first and last character of a string in Javascript.
9 Answers
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SQL Server: What is the difference between CROSS JOIN and FULL OUTER JOIN?
What is the difference between CROSS JOIN and FULL OUTER JOIN in SQL Server?
10 Answers
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What is a race condition?
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A race condition occurs when two or more threads can access shared data and they try to change it at the same time. Because the thread scheduling algorithm can swap between threads at any time, you don't know the order in which the threads will attempt to access the shared data. Therefore, the re...
CSS media queries: max-width OR max-height
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Use a comma to specify two (or more) different rules:
@media screen and (max-width: 995px) , screen and (max-height: 700px) {
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}
From https://developer.mozilla.org/en/CSS/Media_queries/
...In addition, you can combine multiple media queries in a comma-separated list; if any of the ...
How can I calculate the difference between two dates?
How can I calculate the days between 1 Jan 2010 and (for example) 3 Feb 2010?
9 Answers
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What's the pythonic way to use getters and setters?
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What's the pythonic way to use getters and setters?
The "Pythonic" way is not to use "getters" and "setters", but to use plain attributes, like the question demonstrates, and del for deleting (but the names are changed to protect the innocent... builtins):
valu...