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Swapping column values in MySQL
I have a MySQL table with coordinates, the column names are X and Y. Now I want to swap the column values in this table, so that X becomes Y and Y becomes X. The most apparent solution would be renaming the columns, but I don't want to make structure changes since I don't necessarily have permission...
Unique combination of all elements from two (or more) vectors
...s better than the classic expand.grid function because (1) strings are not converted into factors and (2) the sorting is more intuitive:
library(tidyr)
a <- c("ABC", "DEF", "GHI")
b <- c("2012-05-01", "2012-05-02", "2012-05-03", "2012-05-04", "2012-05-05")
crossing(a, b)
# A tibble: 15 x 2...
What is the canonical way to check for errors using the CUDA runtime API?
Looking through the answers and comments on CUDA questions, and in the CUDA tag wiki , I see it is often suggested that the return status of every API call should checked for errors. The API documentation contains functions like cudaGetLastError , cudaPeekAtLastError , and cudaGetErrorString , b...
What is the difference between exit() and abort()?
In C and C++, what is the difference between exit() and abort() ? I am trying to end my program after an error (not an exception).
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Mercurial: Can I rename a branch?
...ms where you can force the users to clone this is a good idea -- or use hg convert instead.
– hochl
Apr 3 '12 at 8:34
5
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git replacing LF with CRLF
...ut something, all text files automatically will have their LF line endings converted to CRLF endings. This allows development of a project across platforms that use different line-ending styles without commits being very noisy because each editor changes the line ending style as the line ending sty...
Comparing date part only without comparing time in JavaScript
...one when you create, you now need to be sure to keep timezone out when you convert back to a string representation. So you can safely use...
toISOString()
getUTCxxx()
getTime() //returns a number with no time or timezone.
.toLocaleDateString("fr",{timeZone:"UTC"}) // whatever locale you want, but A...
Spring - @Transactional - What happens in background?
...hapters to it. I recommend reading the ones on Aspect-Oriented Programming and Transactions, as Spring's declarative transaction support uses AOP at its foundation.
But at a very high level, Spring creates proxies for classes that declare @Transactional on the class itself or on members. The proxy ...
What is the worst gotcha in C# or .NET? [closed]
I was recently working with a DateTime object, and wrote something like this:
61 Answers
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Get boolean from database using Android and SQLite
How can I obtain the value of a boolean field in an SQLite database on Android?
10 Answers
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