大约有 2,193 项符合查询结果(耗时:0.0168秒) [XML]
What is database pooling?
...e connections to multiple servers and multiple user accounts, they may pre-allocate some baseline of connections so some are ready immediately, and they may actually close old connections when the usage pattern quietens down.
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Why are Where and Select outperforming just Select?
...reating a LINQ expression is cheap. Calling delegate functions is cheap. Allocating and looping over an iterator is cheap. But it's even cheaper to not do these things. Thus, if you find that a LINQ statement is the bottleneck in your program, in my experience rewriting it without LINQ will alwa...
Tuples( or arrays ) as Dictionary keys in C#
...s are value types (structs), not reference types, so they avoid the memory allocation and garbage collection costs. Also, they offer conciser and more intuitive syntax, allowing for their fields to be named if you so wish. They also implement the IEquatable<T> interface needed for the dictiona...
smart pointers (boost) explained
...neither transferable nor sharable. It's just usable if you locally need to allocate memory, but be sure it's freed again when it goes out of scope. But it can still be swapped with another scoped_ptr, if you wish to do so.
shared_ptr is a smart pointer that shares ownership (third kind above). It ...
Python: Is it bad form to raise exceptions within __init__?
...n't been properly initialized. Actually it's a very common idiom in C++ to allocate resources in the constructor and deallocate them in the destructor. You suggest that the member object destroys itself (deallocating the resources in its destructor) - then the same issue arises when writing the memb...
SSL certificate rejected trying to access GitHub over HTTPS behind firewall
...test it works by ssh-ing to gitproxy
pti@pti-laptop:~$ ssh github.com
PTY allocation request failed on channel 0
Hi ptillemans! You've successfully authenticated, but GitHub does not provide shell access.
Connection to github.com closed.
pti@pti-laptop:~$
(Note: if you never logged in to g...
Finalize vs Dispose
...uarantee that a finalizer will execute at all on any given instance.
Never allocate memory in finalizers or call virtual methods from finalizers.
Avoid synchronization and raising unhandled exceptions in the finalizers.
The execution order of finalizers is non-deterministic—in other words, you can...
GCC compile error with >2 GB of code
...bal data? If it is the case, I'd restructure the program so that they are allocated dynamically. If the data is initialized, I'd read it from a configuration file.
BTW seeing this:
(.text+0x20): undefined reference to `main'
I think you have another problem.
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Using a custom typeface in Android
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This will work, but pre-ICS it will allocate memory for the fonts for each view you instantiate: code.google.com/p/android/issues/detail?id=9904 A way to fix this is to create a globally-accessible static hashmap of all instantiated fonts: code.google.com/p/and...
When should you use constexpr capability in C++11?
... @alecov Definitly not everything... I/O, syscall and dynamic memory allocation definitly cann't be marked as constexpr Besides, not everything should be constexpr.
– JiaHao Xu
Oct 8 '18 at 7:52
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