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Is there a good reason I see VARCHAR(255) used so often (as opposed to another length)?
...ve to use its "utf8mb4" encoding. But people are much more likely to not know that and go with "utf8", and much more likely to want UTF-8 than any other encoding, so, presto, they wind up with a maximum indexable length of 255 characters in a VARCHAR. Your astoundment notwithstanding.
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Xcode without Storyboard and ARC
...ler = nav;
[self.window makeKeyAndVisible];
return YES;
}
Now,in above example you have to manage memory management manually like ,
self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
[test release];
STEPS FOR REMOVE ARC
1) In ...
JPA OneToMany not deleting child
...e JPA doesn't cater for it.
In part this is because JPA doesn't actually know if it should delete something removed from the collection. In object modeling terms, this is the difference between composition and "aggregation*.
In composition, the child entity has no existence without the parent. A c...
Find Java classes implementing an interface [duplicate]
...functionality to locate the classes that implemented a given interface. I know the functions were hidden in some non-logical place, but they could be used for other classes as the package name implied. Back then I did not need it, so I forgot about it, but now I do, and I can't seem to find the func...
Java Reflection Performance
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so you've just killed the optimiser, so now both versions are slow. Reflection is, therefore, still damn slow.
– gbjbaanb
Feb 13 '09 at 23:39
14
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What is an existential type?
...X they're saying: You can plug in whatever type you want, I don't need to know anything about the type to do my job, I'll only refer to it opaquely as X.
When someone defines an existential type ∃X they're saying: I'll use whatever type I want here; you wont know anything about the type, so you c...
What is the purpose of .PHONY in a Makefile?
...y're not associated with files, e.g.:
.PHONY: clean
clean:
rm -rf *.o
Now make clean will run as expected even if you do have a file named clean.
In terms of Make, a phony target is simply a target that is always out-of-date, so whenever you ask make <phony_target>, it will run, independ...
Captured variable in a loop in C#
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I believe what you are experiencing is something known as Closure http://en.wikipedia.org/wiki/Closure_(computer_science). Your lamba has a reference to a variable which is scoped outside the function itself. Your lamba is not interpreted until you invoke it and once it is i...
Setting property 'source' to 'org.eclipse.jst.jee.server:JSFTut' did not find a matching property
...ans that the <Context> element in Tomcat's server.xml contains an unknown attribute source and that Tomcat doesn't know what to do with this attribute and therefore will ignore it.
Eclipse WTP adds a custom attribute source to the project related <Context> element in the server.xml of T...
What is default color for text in textview?
...nd after that I want to set the color again back to default, but I do not know what is default color, does anyone knows ?
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