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What are the main performance differences between varchar and nvarchar SQL Server data types?
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Usually when people start their answer with the word "Always" then you should ignore everything that comes after that. (Notice I started that statement out with the word "usually" :)
– Brandon Moore
May 4 '12 at 20:07
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Best practice for Django project working directory structure
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When using setup.py, add scripts keyword argument: github.com/elvard/django-start-template/blob/master/project/… I like tmp because it suggests "something temporary" which can be removed anytime. Toplevel locale dir isn't necessary, you can place it anywhere...
How to configure MongoDB Java driver MongoOptions for production use?
...onnections eventually even if the actual query throughput is low (in order words you will see the "conn" statistic in mongostat rise until it hits this number per app server).
There is no need to set this higher than 100 in most cases but this setting is one of those "test it and see" things. Do n...
Why is it necessary to set the prototype constructor?
...ed it was correctly wired up.
Of course, with ES2015 (aka ES6)'s class keyword, most of the time we would have used it, we don't have to anymore, because it's handled for us when we do
class Student extends Person {
}
¹ "...if you're subclassing something that uses it (like Promise or Array) ...
How to return a string value from a Bash function
...control variable in a for loop has the nameref attribute, the list
of words can be a list of shell variables, and a name reference will be⋅
established for each word in the list, in turn, when the loop is executed.
Array variables cannot be given the -n attribute. However, nameref ...
git stash blunder: git stash pop and ended up with merge conflicts
... opinion. Consider editing your answer to put it up front along with a the words DON'T PANIC in large, friendly letters. (+1 already though.) Thanks.
– Patrick M
Jan 28 '16 at 20:34
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What are the use cases for selecting CHAR over VARCHAR in SQL?
...l data. So (assuming you are using a one-byte character set) storing the word "FooBar"
CHAR(6) = 6 bytes (no overhead)
VARCHAR(100) = 8 bytes (2 bytes of overhead)
CHAR(10) = 10 bytes (4 bytes of waste)
The bottom line is CHAR can be faster and more space-efficient for data of relatively the sam...
How much is the overhead of smart pointers compared to normal pointers in C++?
... overhead of smart pointers compared to normal pointers in C++11? In other words, is my code going to be slower if I use smart pointers, and if so, how much slower?
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CROSS JOIN vs INNER JOIN in SQL
...IN returns the Cartesian product of rows from tables in the join. In other words, it will produce rows which combine each row from the first table with each row from the second table.
Inner join
[...] The result of the join can be defined as the outcome of first taking the Cartesian pr...
What is the meaning of the term arena in relation to memory?
...g concept. In one of the later chapters, the author makes heavy use of the word arena , but never defines it. I've searched for the meaning of the word and how it relates to memory, and found nothing. Here are a few contexts in which the author uses the term:
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