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Is it fine to have foreign key as primary key?
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Foreign keys are almost always "Allow Duplicates," which would make them unsuitable as Primary Keys.
Instead, find a field that uniquely identifies each record in the table, or add a new field (either an auto-incrementing integer or a GUID) to act as the p...
Do HttpClient and HttpClientHandler have to be disposed between requests?
... HOLD ON TO THE INSTANCE TO REUSE IT LATER"? For instance, if a method is called repeatedly and creates a new HttpClient instance (even though it's not the recommended pattern in most cases), would it still be correct to say this method should not dispose the instance (that will not be reused)? It c...
“int main (vooid)”? How does that work?
I recently had to type in a small C test program and, in the process, I made a spelling mistake in the main function by accidentally using vooid instead of void .
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How to redirect to previous page in Ruby On Rails?
I have a page that lists all of the projects that has sortable headers and pagination.
7 Answers
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How is Python's List Implemented?
...dynamic array. Practical proof: Indexing takes (of course with extremely small differences (0.0013 µsecs!)) the same time regardless of index:
...>python -m timeit --setup="x = [None]*1000" "x[500]"
10000000 loops, best of 3: 0.0579 usec per loop
...>python -m timeit --setup="x = [None]*100...
Copy and paste content from one file to another file in vi
...wo putty windows open, I am doing "v for visual mode first and then select all the lines and the do a "y" for yanking, not I am doing an alt+tab to get onto the other file and when I do a "p" for put, it only prints a quotation mark.
– macha
Jan 6 '11 at 22:42
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How can I retrieve Id of inserted entity using Entity framework? [closed]
...to ObjectSet and SaveChanges on related ObjectContext. Id will be automatically filled for you:
using (var context = new MyContext())
{
context.MyEntities.Add(myNewObject);
context.SaveChanges();
int id = myNewObject.Id; // Yes it's here
}
Entity framework by default follows each INSERT wi...
How do I get the height and width of the Android Navigation Bar programmatically?
...r). You have to find out separately if and where the navigation bar is actually showing, e.g. by testing for the presence of a physical menu button. Maybe you can find some other way in the Android souce code at android.googlesource.com/platform/frameworks/base/+/…
– user1494...
Take the content of a list and append it to another list
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Take a look at itertools.chain for a fast way to treat many small lists as a single big list (or at least as a single big iterable) without copying the smaller lists:
>>> import itertools
>>> p = ['a', 'b', 'c']
>>> q = ['d', 'e', 'f']
>>> r = ['g', ...
How can I return the current action in an ASP.NET MVC view?
... the advice to add semantic information to the model is a better method in all cases than to rely on route data (controller, action) in your view even if the other answer provides more detail on how to get that data.
– tvanfosson
Apr 28 '16 at 12:34
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