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Django database query: How to get object by id?
Django automatically creates an id field as primary key.
6 Answers
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How to add an integer to each element in a list?
...ition, but if you have a more complex function that you needed to apply to all the elements then map may be a good fit.
In your example it would be:
>>> map(lambda x:x+1, [1,2,3])
[2,3,4]
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What techniques can be used to speed up C++ compilation times?
...ity that takes advantage of caching techniques to speed things up.
Use Parallelism
Many compilers / IDEs support using multiple cores/CPUs to do compilation simultaneously. In GNU Make (usually used with GCC), use the -j [N] option. In Visual Studio, there's an option under preferences to allow it...
What does FETCH_HEAD in Git mean?
...it like doing git fetch without arguments (or git remote update), updating all your remote branches, then running git merge origin/<branch>, but using FETCH_HEAD internally instead to refer to whatever single ref was fetched, instead of needing to name things.
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How to find the installed pandas version
...trouble with some of pandas functionalities. How do I check what is my installation version?
6 Answers
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Add custom messages in assert?
...rk; they’re compile-time constants and their use in this context is trivially optimized away. There is no runtime cost.
– zneak
Aug 9 '19 at 8:46
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How to implement the factory method pattern in C++ correctly
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First of all, there are cases when
object construction is a task complex
enough to justify its extraction to
another class.
I believe this point is incorrect. The complexity doesn't really matter. The relevance is what does. I...
Read a file in Node.js
...leSync--he's in the middle of processing a web request. This answer was totally inappropriate to the question at hand.
– Samuel Neff
Jun 8 '15 at 13:56
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How can I include a YAML file inside another?
...ve added an answer below...hope it helps.
– daveaspinall
Aug 19 '15 at 9:39
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If you're using Rai...
Rails raw SQL example
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and then you'd need to call values on this PG::Result object to get the results array
– jobwat
Mar 26 '14 at 1:00
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