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MySQL select 10 random rows from 600K rows fast
...jan.kneschke.de/projects/mysql/order-by-rand/
For most general case, here is how you do it:
SELECT name
FROM random AS r1 JOIN
(SELECT CEIL(RAND() *
(SELECT MAX(id)
FROM random)) AS id)
AS r2
WHERE r1.id >= r2.id
ORDER BY r1.id ASC...
Converting String to Int with Swift
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Basic Idea, note that this only works in Swift 1.x (check out ParaSara's answer to see how it works in Swift 2.x):
// toInt returns optional that's why we used a:Int?
let a:Int? = firstText.text.toInt() // firstText is UITextField
let b...
RESTfully design /login or /register resources?
...ely harmless effects such as logging, caching, the serving of banner advertisements or incrementing a web counter. [...]
[... H]andling [of GET requests] by the server is not technically limited in any way. Therefore, careless or deliberate programming can cause non-trivial changes on the server. Th...
Trust Store vs Key Store - creating with keytool
...vate/public keys and the trust store only public keys (and represents the list of trusted parties you intend to communicate with). Well, that's my first assumption, so if that's not correct, I probably haven't started very well...
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Java List.add() UnsupportedOperationException
I try to add objects to a List<String> instance but it throws an UnsupportedOperationException .
Does anyone know why?
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ValueError: invalid literal for int() with base 10: ''
... am creating a program that reads a file and if the first line of the file is not blank, it reads the next four lines. Calculations are performed on those lines and then the next line is read. If that line is not empty it continues. However, I am getting this error:
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IllegalStateException: Can not perform this action after onSaveInstanceState with ViewPager
... 11.
}
Don't make the call to super() on the saveInstanceState method. This was messing things up...
This is a known bug in the support package.
If you need to save the instance and add something to your outState Bundle you can use the following:
@Override
protected void onSaveInstanceState(Bu...
how does multiplication differ for NumPy Matrix vs Array classes?
...rix multiplication, you need to use the function matrixmultipy(). I feel this makes the code very unreadable.
8 Answers
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What is the difference between an int and a long in C++?
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It is implementation dependent.
For example, under Windows they are the same, but for example on Alpha systems a long was 64 bits whereas an int was 32 bits. This article covers the rules for the Intel C++ compiler on variab...
How to set the part of the text view is clickable
I have the text " Android is a Software stack ". In this text i want to set the " stack " text is clickable. in the sense if you click on that it will redirected to a new activity(not in the browser).
...