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What's the best practice for primary keys in tables?
...Thanks!
– Lloyd Cotten
Dec 3 '08 at 20:13
4
No, just experience. When dealing with "small" databa...
There is already an open DataReader associated with this Command which must be closed first
...
answered May 19 '11 at 20:21
Ladislav MrnkaLadislav Mrnka
345k5656 gold badges638638 silver badges653653 bronze badges
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Numpy - add row to array
... jknairjknair
3,79111 gold badge1414 silver badges2020 bronze badges
2
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Test if string is a number in Ruby on Rails
...oshua Pinter
34k1717 gold badges188188 silver badges208208 bronze badges
answered Apr 14 '11 at 10:13
Jakob SJakob S
17.6k33 gold ...
How to split a string in shell and get the last field
...e given problem, the answer of William below (stackoverflow.com/a/3163857/520162) also returns 5 if the string is 1:2:3:4:5: (while using the string operators yields an empty result). This is especially handy when parsing paths that could contain (or not) a finishing / character.
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Is the practice of returning a C++ reference variable evil?
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420
In general, returning a reference is perfectly normal and happens all the time.
If you mean:
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How can I create a correlation matrix in R?
... between your matrix x and matrix y. Ex.:
set.seed(1)
x <- matrix(rnorm(20), nrow=5, ncol=4)
y <- matrix(rnorm(15), nrow=5, ncol=3)
COR <- cor(x,y)
COR
image(x=seq(dim(x)[2]), y=seq(dim(y)[2]), z=COR, xlab="x column", ylab="y column")
text(expand.grid(x=seq(dim(x)[2]), y=seq(dim(y)[2])), la...
How to rethrow the same exception in SQL Server
... @@trancount > 0 rollback transaction;
throw;
end catch
Before SQL 2012
begin try
begin transaction;
...
commit transaction;
end try
begin catch
declare @ErrorMessage nvarchar(max), @ErrorSeverity int, @ErrorState int;
select @ErrorMessage = ERROR_MESSAGE() + ' ...
Find row where values for column is maximal in a pandas DataFrame
... C
0 1.232853 -1.979459 -0.573626
1 0.140767 0.394940 1.068890
2 0.742023 1.343977 -0.579745
3 2.125299 -0.649328 -0.211692
4 -0.187253 1.908618 -1.862934
>>> df['A'].argmax()
3
>>> df['B'].argmax()
4
>>> df['C'].argmax()
1
Alternatively you could also use nump...
Twitter Bootstrap vs jQuery UI? [closed]
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edited Nov 6 '14 at 20:58
Preston Bernstein
333 bronze badges
answered Mar 20 '12 at 7:31
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