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Why doesn't C++ have a garbage collector?
...while in C++ RAII is implicit so that the user CANNOT unwittingly make the error (by omitting the using keyword)
3. Smart Pointers
Smart pointers often appear as a silver bullet to handle memory in C++. Often times I have heard: we don't need GC after all, since we have smart pointers.
One could...
INNER JOIN vs LEFT JOIN performance in SQL Server
...bles but possibly entire rows of information. And it happens so nicely, no error messages.
You can be very fast as getting 90% of the needed data and not discover the inner joins have silently removed information. Sometimes inner joins can be faster, but I don't believe anyone making that assumpt...
Possibility of duplicate Mongo ObjectId's being generated in two different collections?
... "abc" }
> db.foo.insert({_id: 'abc', data:'xyz'})
E11000 duplicate key error index: test.foo.$_id_ dup key: { : "abc" }
So, absolutely don't rely on _id's being unique across collections, and since you don't control the ObjectId generation function, don't rely on it.
It's possible to create...
Real life example, when to use OUTER / CROSS APPLY in SQL
... reference the outer table, where INNER JOIN cannot do this(throws compile error). When finding the last two dates, joining is done inside CROSS APPLY ie, WHERE M.ID=D.ID.
2. When we need INNER JOIN functionality using functions.
CROSS APPLY can be used as a replacement with INNER JOIN when we ne...
How to implement a queue using two stacks?
...
This really helped to prevent the timeout errors I was getting during pop. I was placing the elements back in the original stack but there was no need to do that. Kudos!
– Pranit Bankar
Oct 16 '16 at 21:29
...
使用虚拟现实和App Inventor进行实验 · App Inventor 2 中文网
...ptions);
} catch (IOException e) {
Timber.e("Error loading image", e);
}
return true;
}
}
当然，我们不应该忘记活动的生命周期，以及在活动被销毁时清理资源的需要：
@Override
protected void onPause()...
Trusting all certificates using HttpClient over HTTPS
...es getting a really long delay and then a javax.net.ssl.SSLException: Read error:. Any idea? How can I set a timeout if the solution is same as stackoverflow.com/questions/5909308/android-2-3-4-ssl-problem?
– Edwin Evans
Nov 15 '11 at 15:53
...
eval command in Bash and its typical uses
...ments, they are first joined with spaces between them.)
${$n} is a syntax error in bash. Inside the braces, you can only have a variable name, with some possible prefix and suffixes, but you can't have arbitrary bash syntax and in particular you can't use variable expansion. There is a way of sayin...
Update relationships when saving changes of EF4 POCO objects
...Roles.Remove(f)" instead of the "db.ReportRoles.Remove(f)" I would get the error.
report.ReportRoles.ToList.ForEach(Function(f) db.ReportRoles.Remove(f))
Dim newRoles = If(String.IsNullOrEmpty(model.RolesString), New String() {}, model.RolesString.Split(","))
newRoles.ToList.ForEach(Function(f) db....
What is a lambda expression in C++11?
...that if the number of lines is smaller then there is a less chance to make errors in it (I'm also think so)
Example of usage
auto x = [=](int arg1){printf("%i", arg1); };
void(*f)(int) = x;
f(1);
x(1);
Extras about lambdas, not covered by question. Ignore this section if you're not interest
1...