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MySQL InnoDB not releasing disk space after deleting data rows from table
... 2M data rows. When I deleted data rows from the table, it did not release allocated disk space. Nor did the size of the ibdata1 file reduce after running the optimize table command.
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Check for column name in a SqlDataReader object
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You're enumerating the field names multiple times / allocating another array to scan with a contains, this would be much less performant in high traffic code.
– Chad Grant
Oct 4 '19 at 17:44
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Running Command Line in Java [duplicate]
...tter than Runtime.getRuntime().exec(). This is for a couple of reasons: it tokenizes better the arguments, and it also takes care of the error standard output (check also here).
ProcessBuilder builder = new ProcessBuilder("cmd", "arg1", ...);
builder.redirectErrorStream(true);
final Process process...
Finalize vs Dispose
...uarantee that a finalizer will execute at all on any given instance.
Never allocate memory in finalizers or call virtual methods from finalizers.
Avoid synchronization and raising unhandled exceptions in the finalizers.
The execution order of finalizers is non-deterministic—in other words, you can...
Swap key with value JSON
...sers/markus/Entwicklung/IT1_Beleg/public/es6/vokabeltrainer.js: Unexpected token (53:45) 51 | if (btoa) { 52 | entries = Object.entries(entries) > 53 | .reduce((obj, [key, value]) => ({...obj, [value]: key}), {}); | ...
How to determine if an NSDate is today?
...me for the second date and compare:
NSCalendar * gregorian = [[NSCalendar alloc]
initWithCalendarIdentifier:NSGregorianCalendar];
NSDateComponents * components =
[gregorian components:
(NSYearCalendarUnit|NSMonthCalendarUnit|NSDayCalendarUnit)
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Safely turning a JSON string into an object
...ill see an error thrown in the console with the dreaded "Error: unexpected token 'x'".
var data;
try {
data = JSON.parse(jqxhr.responseText);
} catch (_error) {}
data || (data = {
message: 'Server error, please retry'
});
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What is the difference between `new Object()` and object literal notation?
...re there are differences between the two syntaxes when you get into memory allocation.
– newshorts
May 20 '15 at 0:29
2
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iPhone viewWillAppear not firing
... setting up the view controllers on the respective controller (right after allocation). From then on, it correctly called these methods on its child view controllers.
My hierarchy is like this:
window
UITabBarController (subclass of)
UIViewController (subclass of) // <-- manually ca...
Java String - See if a string contains only numbers and not letters
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If you look at the code of toCharArray, it is allocating a char array and copying the chars (i think that could be expensive). What about if you just iterate the string using an index and charAt, would it be faster? Would be interesting also if you could add the soluti...