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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 = ...
How do I format a string using a dictionary in python-3.x?
...3). In many languages, it is known as splat operator. In JavaScript, it's called spread operator. In python, there is no particular name given to this operator.
– abhisekp
Apr 15 '17 at 12:01
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How do I get indices of N maximum values in a NumPy array?
...t been able to find one.
If this solution turns out to be too slow (especially for small n), it may be worth looking at coding something up in Cython.
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Receive JSON POST with PHP
...ontents('php://input'), true);
This will save you the hassle of changing all $_POST to something else and allow you to still make normal post requests if you wish to take this line out.
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What is the difference between background and background-color
...background will supercede all previous background-color, background-image, etc. specifications. It's basically a shorthand, but a reset as well.
I will sometimes use it to overwrite previous background specifications in template customizations, where I would want the following:
background: white u...
how to generate migration to make references polymorphic
...ter of polymorphic, like: t.referencesp :imagable, treferenceso :imagable, etc.
– OzBarry
Apr 7 '15 at 18:09
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How to find the Number of CPU Cores via .NET/C#?
...sical processors
Number of cores
Number of logical processors.
These can all be different; in the case of a machine with 2 dual-core hyper-threading-enabled processors, there are 2 physical processors, 4 cores, and 8 logical processors.
The number of logical processors is available through the En...
How to Free Inode Usage?
...age is 100% (using df -i command).
However after deleting files substantially, the usage remains 100%.
15 Answers
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How can Xml Documentation for Web Api include documentation from beyond the main project?
...gration into your Web Api projects appears to only handle situations where all of your API types are part of your WebApi project. In particular, it discusses how to reroute the XML documentation to App_Data/XmlDocument.xml and uncommenting a line in your config that will consume that file. This ...
What are some compelling use cases for dependent method types?
...b: M) = 0;class CI extends C{type A=Int};class CS extends C{type A=String} etc.
– nafg
Oct 7 '13 at 23:26
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