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Multi-statement Table Valued Function vs Inline Table Valued Function
...e compiler cannot use any table statistics on the tables in the MSTVF. So, all things being equal, (which they rarely are), the ITVF will perform better than the MSTVF. In my tests, the performance difference in completion time was negligible however from a statistics standpoint, it was noticeable.
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Python != operation vs “is not”
...right hand side and the left hand side are the very same object. No methodcalls are done, objects can't influence the is operation.
You use is (and is not) for singletons, like None, where you don't care about objects that might want to pretend to be None or where you want to protect against object...
String concatenation: concat() vs “+” operator
...then throwing it away when you create the final String. In practice memory allocation is surprisingly fast.
Update: As Pawel Adamski notes, performance has changed in more recent HotSpot. javac still produces exactly the same code, but the bytecode compiler cheats. Simple testing entirely fails bec...
'printf' vs. 'cout' in C++
...letely on operator overloading, so there is no issue with custom formats - all you do is define a subroutine taking std::ostream as the first argument and your type as second. As such, there are no namespace problems - as long you have a class (which isn't limited to one character), you can have wor...
Date vs DateTime
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Unfortunately, not in the .Net BCL. Dates are usually represented as a DateTime object with the time set to midnight.
As you can guess, this means that you have all the attendant timezone issues around it, even though for a Date object you'd want absolutely no timezone han...
Java Desktop application: SWT vs. Swing [closed]
...ava library, no need for
additional native libraries
works the same way on all platforms
Integrated GUI Editor in Netbeans and Eclipse
good online tutorials by Sun/Oracle
Supported by official java extensions (like java OpenGL)
Cons Swing:
Native look and feel may behave
different from the real...
Greenlet Vs. Threads
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Greenlets provide concurrency but not parallelism. Concurrency is when code can run independently of other code. Parallelism is the execution of concurrent code simultaneously. Parallelism is particularly useful when there's a lot of work to be done in userspace, an...
Visual SVN 安装及客户端使用 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...负责代码编写,所以也是只读权限。而Developer1和manager1是开发人员和项目经理,自然具有读、写的权限。
在实际的项目开发过程中,Developer和tester往往不可能只有一个人,这时候使用组来授权更加方便,这个大家可以自己练习...
PHP: exceptions vs errors?
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Exceptions are thrown - they are intended to be caught. Errors are generally unrecoverable. Lets say for instance - you have a block of code that will insert a row into a database. It is possible that this call fails (duplicate ID) - you will want to have a "Error" which in this case is an "Exc...
What is the difference between typeof and instanceof and when should one be used vs. the other?
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@Luke generally a bad idea to use "new String" like this. that creates a "string object" rather than a string primitive. see section here developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/…
– Colin D
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