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Is there a REAL performance difference between INT and VARCHAR primary keys?
...ary key, then do it.
Don't use either strategy for all tables in your database. It's likely that in some cases, a natural key is better, but in other cases a surrogate key is better.
Other folks make a good point that it's rare in practice for a natural key to never change or have duplicates, s...
mmap() vs. reading blocks
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Keep in mind that using any advice based on hardware and software from the 2000s, without testing it today would be a very suspect approach. Also, while many of the facts about mmap vs read() in that thread are still true as they were in the past, the overall ...
Pass an array of integers to ASP.NET Web API?
... provide a default constructor that pushes the type definition down to the base class: public CommaDelimitedArrayModelBinder() : base(typeof(CommaDelimitedArrayModelBinder)) { }.
– sliderhouserules
Jan 11 '16 at 22:49
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Smart pointers: who owns the object? [closed]
...ct that must be accessible from objects nested in it (usually as a virtual base class). This could be solved by passing a weak_ptr to them, but it doesn't have a shared_ptr to itself. As it knows these objects wouldn't live longer than him, it passes a hub_ptr to them (it's just a template wrapper t...
Moving decimal places over in a double
...ass, we were asked in general what numbers can be exactly represented in a base.
For base=p1^n1*p2^n2... you can represent any N where N=n*p1^m1*p2^m2.
Let base=14=2^1*7^1... you can represent 1/7 1/14 1/28 1/49 but not 1/3
I know about financial software -- I converted Ticketmaster's financial r...
How does Spring Data JPA differ from Hibernate for large projects?
...r *Impl classes automatically now):
@Configuration
@EnableJpaRepositories(basePackages = {"com.examples.repositories"})
@EnableTransactionManagement
public class MyConfiguration {
}
jpa-repositories.xml - tell Spring where to find your repositories. Also tell Spring to look for custom repositorie...
How can I multiply and divide using only bit shifting and adding?
... = 21 * 5 (Same as initial expression)
(_2 means base 2)
As you can see, multiplication can be decomposed into adding and shifting and back again. This is also why multiplication takes longer than bit shifts or adding - it's O(n^2) rather than O(n) in the number of bits. R...
How can I avoid running ActiveRecord callbacks?
... that also works while creating an object
class Person < ActiveRecord::Base
attr_accessor :skip_some_callbacks
before_validation :do_something
after_validation :do_something_else
skip_callback :validation, :before, :do_something, if: :skip_some_callbacks
skip_callback :validation, :a...
Best practices to handle routes for STI subclasses in rails
...45908, using this method will enable you to use "form_for".
ActiveRecord::Base#becomes
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How to check if an activity is the last one in the activity stack for an application?
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Hope this will help new beginners, Based above answers which works for me fine, i am also sharing code snippet so it will be easy to implement.
solution : i used isTaskRoot() which return true if current activity is only activity in your stack and other than ...