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Which SQL query is faster? Filter on Join criteria or Where clause?
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Performance-wise, they are the same (and produce the same plans)
Logically, you should make the operation that still has sense if you replace INNER JOIN with a LEFT JOIN.
In your very case this will look like this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x
ON x.TableAID = ...
Accessing private member variables from prototype-defined functions
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No, there's no way to do it. That would essentially be scoping in reverse.
Methods defined inside the constructor have access to private variables because all functions have access to the scope in which they were defined.
Methods defined on a prototype are not defin...
What is the _references.js used for?
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In VS 11, Visual Studio will give you intellisense from all files
that have references in the “_references.js” file.
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How to use C++ in Go
In the new Go language, how do I call C++ code? In other words, how can I wrap my C++ classes and use them in Go?
12 Answ...
An error occurred while validating. HRESULT = '8000000A'
...t item.
We've run into this as well, and had a very unsatisfying support call on this issue with Microsoft. Long story short: it's a known issue, it won't be solved, and Microsoft advises to move away from Visual Studio Setup projects (.vdproj).
We've worked around this issue by triggering the MSI...
How do I provide custom cast support for my class?
...ou want users to have to cast it or whether you want it to happen automagically. Generally, one direction will always work, that's where you use implicit, and the other direction can sometimes fail, that's where you use explicit.
The syntax is like this:
public static implicit operator dbInt64(Byt...
What is the difference between String.Empty and “” (empty string)?
...ich makes string.Empty more efficient.
In version 2.0 and later of .NET, all occurrences of "" refer to the same string literal, which means "" is equivalent to .Empty, but still not as fast as .Length == 0.
.Length == 0 is the fastest option, but .Empty makes for slightly cleaner code.
See the ...
What is a singleton in C#?
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A singleton is a class which only allows one instance of itself to be created - and gives simple, easy access to said instance. The singleton premise is a pattern across software development.
There is a C# implementation "Implementing the Singleton Pattern i...
Installing older version of R package
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To install an older version of a package from source (within R):
packageurl <- "http://cran.r-project.org/src/contrib/Archive/ggplot2/ggplot2_0.9.1.tar.gz"
install.packages(packageurl, repos=NULL, type="source")
If this doesn'...
How do you read from stdin?
I'm trying to do some of the code golf challenges, but they all require the input to be taken from stdin . How do I get that in Python?
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