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CHECK constraint in MySQL is not working
...GER `test_before_insert` BEFORE INSERT ON `Test`
FOR EACH ROW
BEGIN
IF CHAR_LENGTH( NEW.ID ) < 4 THEN
SIGNAL SQLSTATE '12345'
SET MESSAGE_TEXT := 'check constraint on Test.ID failed';
END IF;
END$$
DELIMITER ;
Prior to MySQL 5.5 you had to cause an error, e.g. ca...
Difference between framework vs Library vs IDE vs API vs SDK vs Toolkits? [closed]
... (software development kit) is a library or group of libraries (often with extra tool applications, data files and sample code) that aid you in developing code that uses a particular system (e.g. extension code for using features of an operating system (Windows SDK), drawing 3D graphics via a partic...
How do I expand a tuple into variadic template function's arguments?
...{
typedef void (T::*F)( Args... args );
public:
Message( const std::string& name,
T& obj,
F pFunc,
Args... args );
private:
virtual void doDispatch( );
T* pObj_;
F pFunc_;
std::tr1::tuple<Args...> args_;
};
//----------------------...
How to vertically center content with variable height within a div?
...o element: CSS-Tricks: Centering in the Unknown.
It doesn’t require any extra markup and seems to work extremely well. I couldn’t use the display: table method because table elements don’t obey the max-height property.
.block {
height: 300px;
text-align: center;
background: #c0...
Error-Handling in Swift-Language
...in AFNetworking:
var sessionManager = AFHTTPSessionManager(baseURL: NSURL(string: "yavin4.yavin.planets"))
sessionManager.HEAD("/api/destoryDeathStar", parameters: xwingSquad,
success: { (NSURLSessionDataTask) -> Void in
println("Success")
},
failure:{ (NSURLSessionDataTask, ...
Convert two lists into a dictionary
...
dict([(k, v) for k, v in zip(keys, values)])
In the first two cases, an extra layer of non-operative (thus unnecessary) computation is placed over the zip iterable, and in the case of the list comprehension, an extra list is unnecessarily created. I would expect all of them to be less performant,...
How to preventDefault on anchor tags?
...gs (<a></a>) to see if their href attribute is either an empty string ("") or a hash ('#') or there is an ng-click assignment. If it finds any of these conditions, it catches the event and prevents the default behavior.
The only down side is that it runs this directive for all anchor t...
How to change checkbox's border style in CSS?
...
Opera lets you style checkboxes without any extra hackery - I would leave off the -o-appearance style. -moz-appearance and -webkit-appearance are great, though.
– Neall
Oct 6 '10 at 15:18
...
Queue.Queue vs. collections.deque
... for high-speed inter-thread communication.
In fact the heavy usage of an extra mutex and extra method ._get() etc. method calls in Queue.py is due to backwards compatibility constraints, past over-design and lack of care for providing an efficient solution for this important speed bottleneck issue...
Handle file download from ajax post
...p that sends ajax POST requests to a certain URL. Response might be a JSON string or it might be a file (as an attachment). I can easily detect Content-Type and Content-Disposition in my ajax call, but once I detect that the response contains a file, how do I offer the client to download it? I've re...