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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...
NOT IN vs NOT EXISTS
...der Details] contains any NULL ProductIds is to return no results. See the extra anti semi join and row count spool to verify this that is added to the plan.
If Products.ProductID is also changed to become NULL-able the query then becomes
SELECT ProductID,
ProductName
FROM Products p
WH...
Container-fluid vs .container
...s as you change the width of your window/browser by any amount, leaving no extra empty space on the sides ever, unlike how .container does. (Hence the naming: "fluid" as opposed to "digital", "discrete", "chunked", or "quantized").
.container resizes in chunks at several certain widths. In other wo...
(Mac) -bash: __git_ps1: command not found
...rompt will change to "os ". To change "os" to something else, modify "os" string in export PS1 line.
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What is stability in sorting algorithms and why is it important?
...r if you have two input lists A,B which are identical except list B has an extra entry, the outputs for a stable sort will be identical except that B has that same extra entry. And +1 for last pgph.
– greggo
Feb 10 '13 at 1:43
...
How do you read from stdin?
... help on the builtin input from Python 3:
input(prompt=None, /)
Read a string from standard input. The trailing newline is stripped.
The prompt string, if given, is printed to standard output without a
trailing newline before reading input.
If the user hits EOF (*nix: Ctrl...
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_;
};
//----------------------...
Get the first item from an iterable that matches a condition
...for x in the_iterable if x > 3), default_value)
Note that you need an extra pair of parentheses around the generator expression in this case − they are needed whenever the generator expression isn't the only argument.
I see most answers resolutely ignore the next built-in and so I assume tha...
How to unzip a file using the command line? [closed]
...zip
Complete set of options for the jar tool available here.
Examples:
Extract jar file
jar x[v]f jarfile [inputfiles] [-Joption]
jar x[v] [inputfiles] [-Joption]
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Should I always return IEnumerable instead of IList?
...ormation but once again, why would you throw away information? If you know extra information about something, pass it on.
– Mel
Oct 20 '11 at 12:13
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