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NOT IN vs NOT EXISTS
...nt to NOT EXISTS when it comes to null.
This post explains it very well
http://sqlinthewild.co.za/index.php/2010/02/18/not-exists-vs-not-in/
When the subquery returns even one null, NOT IN will not match any
rows.
The reason for this can be found by looking at the details of what the
...
Simple example of threading in C++
...ck and was instrumental in hammering out the c++0x standard on the topic.
http://www.hpl.hp.com/techreports/2004/HPL-2004-209.html
That said there are several cross-platform thread C++ libraries that work just fine in practice. Intel thread building blocks contains a tbb::thread object that closel...
Sleep Command in T-SQL?
...eUploader: {
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What is a Y-combinator? [closed]
...
I've lifted this from http://www.mail-archive.com/boston-pm@mail.pm.org/msg02716.html which is an explanation I wrote several years ago.
I'll use JavaScript in this example, but many other languages will work as well.
Our goal is to be able to w...
hash function for string
...t GCC uses an implementation of "MurmurHashUnaligned2", by Austin Appleby (http://murmurhash.googlepages.com/).
In the file "gcc/libstdc++-v3/libsupc++/hash_bytes.cc", here (https://github.com/gcc-mirror/gcc/blob/master/libstdc++-v3/libsupc++/hash_bytes.cc), I found the implementations. Here's the ...
Python using enumerate inside list comprehension
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What is difference between CrudRepository and JpaRepository interfaces in Spring Data JPA?
...and delete records in a batch
When to use which interface:
According to http://jtuts.com/2014/08/26/difference-between-crudrepository-and-jparepository-in-spring-data-jpa/
Generally the best idea is to use CrudRepository or PagingAndSortingRepository depending on whether you need sorting and pag...
Passing Objects By Reference or Value in C#
... so, you have to use ref in method.
Following link give you better idea.
http://dotnetstep.blogspot.com/2008/09/passing-reference-type-byval-or-byref.html
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Visual Studio support for new C / C++ standards?
...f public replies to this, most of them blaming their users. Like this one:
https://devblogs.microsoft.com/cppblog/iso-c-standard-update/
Now, the Visual C++ compiler team receives the occasionally question as to why we haven’t implemented C99. It’s really based on interest from our users. Whe...
How can I return an empty IEnumerable?
...ndFriends()
{
//Many thanks to Rex-M for his help with this one.
//http://stackoverflow.com/users/67/rex-m
if (userExists)
{
foreach(var user in doc.Descendants("user"))
{
yield return new Friend
{
ID = user.Element("id"...