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Why use multiple columns as primary keys (composite primary key)
...going to, in general, perform more poorly than a surrogate key'. Often an extra query is required to get the surrogate key of a relationship when you consider it. At which point it's a full extra round trip slower performance wise.
– ttugates
Apr 19 '19 at 20...
How to get the concrete class name as a string? [duplicate]
...ing for a way to get the concrete class name for an instance variable as a string.
3 Answers
...
Iterate keys in a C++ map
...e <iostream>
#include <map>
int main()
{
std::map<std::string, int> myMap;
myMap["one"] = 1;
myMap["two"] = 2;
myMap["three"] = 3;
for ( const auto &myPair : myMap ) {
std::cout << myPair.first << "\n";
}
}
...
How to get the request parameters in Symfony 2?
... uses, but it actually makes more sense. $_GET data is data from the query string (no GET request needed at all) and $_POST data is data from the request body (does not have to be a POST request either, could be PUT).
– igorw
Mar 20 '12 at 15:43
...
Convert JavaScript string in dot notation into an object reference
...pvotes, I am also somewhat horrified. If one needs to convert dot-notation strings like "x.a.b.c" into references, it could (maybe) be a sign that there is something very wrong going on (unless maybe you're performing some strange deserialization).
That is to say, novices who find their way to ...
How to check internet access on Android? InetAddress never times out
... have a remote glue about internet access, without this permission?)
Extra: One-shot AsyncTask Example
class InternetCheck extends AsyncTask<Void,Void,Boolean> {
private Consumer mConsumer;
public interface Consumer { void accept(Boolean internet); }
public InternetCheck...
Sending HTML email using Python
...ddress, recipient's address
# and message to send - here it is sent as one string.
s.sendmail(me, you, msg.as_string())
s.quit()
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Mimicking sets in JavaScript?
I'm working in JavaScript. I'd like to store a list of unique , unordered string values, with the following properties:
7 ...
What are the differences in die() and exit() in PHP?
... have two exit functions now! Let's make it so that they both
can take a string or integer as an argument and make them identical!"
The end result is that this didn't really make things any "easier",
just more confusing. C and Perl coders will continue to use exit() to
toss an integer exi...
Purpose of Python's __repr__
... be a representation readable for the Python interpreter (i.e. feeding the string to the interpreter should recreate the object). If an object does not have a __str__ method, however, __repr__ is used instead. Also as noted: this example actually prints the __str__ method of self.x and self.y: %r sh...