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Multiple Indexes vs Multi-Column Indexes
I've just been adding an Index to a table in SQL Server 2005 and it got me thinking. What is the difference between creating 1 index and defining multiple columns over having 1 index per column you want to index.
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Error type 3 Error: Activity class {} does not exist
I have an IntelliJ Android project, that I successfully imported to Android Studio 0.4.0. It works perfectly if I don't change anything in manifest. However, when I want to change the launcher activity and run, it fails with this error:
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How to add leading zeros?
...s of 10 width 8 too.
anim <- 25499:25504
x <- 10 ^ (0:5)
paste (and it's variant paste0) are often the first string manipulation functions that you come across. They aren't really designed for manipulating numbers, but they can be used for that. In the simple case where we always have t...
How can I force division to be floating point? Division keeps rounding down to 0?
I have two integer values a and b , but I need their ratio in floating point. I know that a < b and I want to calculate a / b , so if I use integer division I'll always get 0 with a remainder of a .
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How to use concerns in Rails 4
...4 project generator now creates the directory "concerns" under controllers and models. I have found some explanations about how to use routing concerns, but nothing about controllers or models.
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How may I sort a list alphabetically using jQuery?
I'm a bit out of my depth here and I'm hoping this is actually possible.
10 Answers
10...
Difference between reduce and foldLeft/fold in functional programming (particularly Scala and Scala
Why do Scala and frameworks like Spark and Scalding have both reduce and foldLeft ? So then what's the difference between reduce and fold ?
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How to convert an int to string in C?
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EDIT: As pointed out in the comment, itoa() is not a standard, so better use sprintf() approach suggested in the rivaling answer!
You can use itoa() function to convert your integer value to a string.
Here is an example:
int num = 321;
char snum[5];
// convert 123 to string...
Generating a random & unique 8 character string using MySQL
...nsists of two very different sub-problems:
the string must be seemingly random
the string must be unique
While randomness is quite easily achieved, the uniqueness without a retry loop is not. This brings us to concentrate on the uniqueness first. Non-random uniqueness can trivially be achieved w...
Fastest way to list all primes below N
...t William Hanks for primesfrom2to, primesfrom3to, rwh_primes, rwh_primes1, and rwh_primes2.
Of the plain Python methods tested, with psyco, for n=1000000,
rwh_primes1 was the fastest tested.
+---------------------+-------+
| Method | ms |
+---------------------+-------+
| rwh_prime...