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What is the difference between char, nchar, varchar, and nvarchar in SQL Server?
...orage.
– Wim ten Brink
Nov 2 '09 at 10:41
10
It is collation dependant whether or not the n... ve...
Lists: Count vs Count() [duplicate]
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answered Nov 4 '10 at 15:22
BFreeBFree
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What is “lifting” in Scala?
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edited Jul 31 '13 at 10:38
answered Jul 31 '13 at 8:31
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What is the difference between RegExp’s exec() function and String’s match() function?
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Alex CiminianAlex Ciminian
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Best exception for an invalid generic type argument
I'm currently writing some code for UnconstrainedMelody which has generic methods to do with enums.
11 Answers
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filter for complete cases in data.frame using dplyr (case-wise deletion)
...305 1.022891 1.013779 0.9948659 4.668691 20
# rowSums 2.281002 2.377807 2.420615 2.3467519 5.223077 20
# filter 1.000000 1.000000 1.000000 1.0000000 1.000000 20
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What is the advantage of using forwarding references in range-based for loops?
...ider:
#include <vector>
int main()
{
std::vector<bool> v(10);
for (auto& e : v)
e = true;
}
This doesn't compile because rvalue vector<bool>::reference returned from the iterator won't bind to a non-const lvalue reference. But this will work:
#include <...
Split delimited strings in a column and insert as new rows [duplicate]
... a
2 1 b
3 1 c
4 2 a
5 2 c
6 3 b
7 3 d
8 4 e
9 4 f
10 . .
Update 2017: note the separate_rows function as described by @Tif below.
It works so much better, and it allows to "unnest" multiple columns in a single statement:
> head(mydf)
geneid chrom sta...
When to use EntityManager.find() vs EntityManager.getReference() with JPA
... Arthur RonaldArthur Ronald
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Linq: adding conditions to the where clause conditionally
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Reed CopseyReed Copsey
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