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What are the differences between Helper and Utility classes?
...ts more common.
A Utility class is understood to only have static methods and be stateless. You would not create an instance of such a class.
A Helper can be a utility class or it can be stateful or require an instance be created. I would avoid this if possible.
If you can make the name more spe...
Storing time-series data, relational or non?
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Definitely Relational. Unlimited flexibility and expansion.
Two corrections, both in concept and application, followed by an elevation.
Correction
It is not "filtering out the un-needed data"; it is selecting only the needed data. Yes, of course, if you have an Ind...
How do SO_REUSEADDR and SO_REUSEPORT differ?
The man pages and programmer documentations for the socket options SO_REUSEADDR and SO_REUSEPORT are different for different operating systems and often highly confusing. Some operating systems don't even have the option SO_REUSEPORT . The WEB is full of contradicting information regarding th...
Why does ++[[]][+[]]+[+[]] return the string “10”?
This is valid and returns the string "10" in JavaScript ( more examples here ):
9 Answers
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what is the difference between a portlet and a servlet?
I am asked to work on portlets and portals.
5 Answers
5
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How to compare two floating point numbers in Bash?
...) )); then
…
fi
Explanation
Piping through the basic calculator command bc returns either 1 or 0.
The option -l is equivalent to --mathlib; it loads the standard math library.
Enclosing the whole expression between double parenthesis (( )) will translate these values to respectively true or...
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
...
Python if-else short-hand [duplicate]
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The most readable way is
x = 10 if a > b else 11
but you can use and and or, too:
x = a > b and 10 or 11
The "Zen of Python" says that "readability counts", though, so go for the first way.
Also, the and-or trick will fail if you put a variable instead of 10 and it evaluates to Fals...
Determine if the device is a smartphone or tablet? [duplicate]
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This subject is discussed in the Android Training:
Use the Smallest-width Qualifier
If you read the entire topic, they explain how to set a boolean value in a specific value file (as res/values-sw600dp/attrs.xml):
<resources>
<bool name="isTa...
Why does Lua have no “continue” statement?
I have been dealing a lot with Lua in the past few months, and I really like most of the features but I'm still missing something among those:
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