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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...
PowerShell Script to Find and Replace for all Files with a Specific Extension
... I would like to add that testing the solutions provided out all worked, but this one was the easiest for readability. I was able to hand this to a co-worker and he could easily understand what was going on. Thanks for the assistance.
– Brandon
Ma...
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 ...
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...
How to count total lines changed by a specific author in a Git repository?
...--author="<authorname>" --oneline --shortstat
This gives stats for all commits on the current HEAD. If you want to add up stats in other branches you will have to supply them as arguments to git log.
For passing to a script, removing even the "oneline" format can be done with an empty log f...
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.
For More Info
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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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Convert nested Python dict to object?
...; s.a
1
>>> s.b
{'c': 2}
>>> s.c
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: 'MyStruct' object has no attribute 'c'
>>> s.d
['hi']
The alternative (original answer contents) is:
class Struct:
def __init__(self...
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'...