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Can you have if-then-else logic in SQL? [duplicate]
... in dbs it is not optimal because this syntax is procedural - it would be orders of magnitude slower than a proper set based query.
– mson
Feb 28 '13 at 13:42
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What are sessions? How do they work?
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Because HTTP is stateless, in order to associate a request to any other request, you need a way to store user data between HTTP requests.
Cookies or URL parameters ( for ex. like http://example.com/myPage?asd=lol&boo=no ) are both suitable ways to ...
What does (function($) {})(jQuery); mean?
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Type 3, in order to work would have to look like this:
(function($){
//Attach this new method to jQuery
$.fn.extend({
//This is where you write your plugin's name
'pluginname': function(_options) {
...
Does a foreign key automatically create an index?
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Say you have a big table called orders, and a small table called customers. There is a foreign key from an order to a customer. Now if you delete a customer, Sql Server must check that there are no orphan orders; if there are, it raises an error.
To check ...
What exactly are unmanaged resources?
...nections
Unmanaged memory
In XNA: vertex buffers, index buffers, textures, etc.
Normally you want to release those unmanaged resources before you lose all the references you have to the object managing them. You do this by calling Dispose on that object, or (in C#) using the using statement which...
Get the first key name of a javascript object [duplicate]
..." key in a hash (Javascript calls them objects). They are fundamentally unordered. Do you mean just choose any single key:
for (var k in ahash) {
break
}
// k is a key in ahash.
share
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imp...
Exception thrown in NSOrderedSet generated accessors
... implementation of the add object setter to append correctly to a NSMutableOrderedSet.
- (void)addSubitemsObject:(SubItem *)value {
NSMutableOrderedSet* tempSet = [NSMutableOrderedSet orderedSetWithOrderedSet:self.subitems];
[tempSet addObject:value];
self.subitems = tempSet;
}
Reassi...
Why is address zero used for the null pointer?
... code you will still continue to designate null-pointers by constant 0. In order to assign a null-pointer value to a given pointer, you will continue to use expressions like p = 0. It is the compiler's responsibility to realize what you want and translate it into the proper null-pointer value repres...
Setting variable to NULL after free
...roblem in such cases is to review and rethink the structure of the code in order to avoid the situation when the same pointer is passed to free more than once. In such cases setting the pointer to NULL and considering the problem "fixed" is nothing more than an attempt to sweep the problem under the...
Why should I use a pointer rather than the object itself?
...y, you shouldn't abuse it. So here are some disadvantages in no particular order:
It is error-prone. Manual memory allocation is dangerous and you are prone to leaks. If you are not proficient at using the debugger or valgrind (a memory leak tool), you may pull your hair out of your head. Luckily ...