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Why historically do people use 255 not 256 for database field magnitudes?
You often see database fields set to have a magnitude of 255 characters, what is the traditional / historic reason why? I assume it's something to do with paging / memory limits, and performance but the distinction between 255 and 256 has always confused me.
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What are the best practices for catching and re-throwing exceptions?
...bvious meaningful action is to handle the exception, e.g. by displaying an error message and aborting the operation:
try {
$connect = new CONNECT($db, $user, $password, $driver, $host);
}
catch (Exception $e) {
echo "Error while connecting to database!";
die;
}
Logging or partial clea...
Why should casting be avoided? [closed]
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Casting errors are always reported as run-time errors in java. Using generics or templating turns these errors into compile-time errors, making it much easier to detect when you have made a mistake.
As I said above. This isn't to sa...
How do I show/hide a UIBarButtonItem?
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Save your button in a strong outlet (let's call it myButton) and do this to add/remove it:
// Get the reference to the current toolbar buttons
NSMutableArray *toolbarButtons = [self.toolbarItems mutableCopy];
// This is how you remove the button from the toolbar and ...
Difference between two dates in MySQL
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SELECT TIMESTAMPDIFF(HOUR,NOW(),'2013-05-15 10:23:23')
calculates difference in hour.(for days--> you have to define day replacing hour
SELECT DATEDIFF('2012-2-2','2012-2-1')
SELECT TO_DAYS ('2012-2-2')-TO_DAYS('2012-2-1')
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Mocking python function based on input arguments
...h keywords in you production code or this approach won't work. You get the error: got multiple values for argument.
– Erik Kalkoken
Mar 6 at 10:43
add a comment
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iPhone get SSID without private library
...t to add/link the [+]framework to your project. If you see weird compiling errors when using this method that is probably your problem. To e.g. get the SSID from the returned dictionary use // Getting a dictionary object containing the information of the network the iPhone is connected to NS...
Best way to define error codes/strings in Java?
...web service in Java, and I am trying to figure out the best way to define error codes and their associated error strings . I need to have a numerical error code and an error string grouped together. Both the error code and error string will be sent to the client accessing the web service. For examp...
What exactly are DLL files, and how do they work?
...elete or rename the DLL and watch how the loader will report a missing DLL error when you try to run the executable.
Hence the name Dynamic Link Library, parts of the linking process is being done dynamically at run time by the executable loader.
One a final note, if you don't link to the DLL then...
Word-wrap in an HTML table
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@ewomac yeah, sometimes I just have to ignore the VS2010 errors about HTML/CSS if I know it will work in the browser.
– Marc Stober
Aug 11 '11 at 16:19
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