大约有 47,000 项符合查询结果（耗时：0.0572秒） [XML]
Is the “struct hack” technically undefined behavior?
...ous pointer arithmetic could then be made to trap - see e.g. CCured. On a more philosophical level, it doesn't matter whether no possible implementation could catch you, it's still undefined behavior (there are, iirc, cases of undefined behavior that would require an oracle for the Halting Problem ...
How to return an empty ActiveRecord relation?
...
|
show 7 more comments
77
...
WAMP/XAMPP is responding very slow over localhost
...Pro user you are entitled to have downgrade rights to Windows 7. Read here more about this. For me that was the only solution that really did the job properly.
Good luck!
share
|
improve this answ...
Jquery selector input[type=text]')
...on:
$('.sys').find('input[type=text],select').each(function() {...})
Or more concisely, pass in the context argument:
$('input[type=text],select', '.sys').each(function() {...})
Note: Internally jQuery will convert the above to find() equivalent
http://api.jquery.com/jQuery/
Internally, s...
Does the join order matter in SQL?
... FULL) OUTER joins, yes, the order matters - and (updated) things are much more complicated.
First, outer joins are not commutative, so a LEFT JOIN b is not the same as b LEFT JOIN a
Outer joins are not associative either, so in your examples which involve both (commutativity and associativity) pr...
Value Change Listener to JTextField
...ntioned in Jean-Marc Astesana's answer, where the document sometimes fires more events than it needs to.
Anyway, this method lets you replace annoying code which looks like this:
someTextBox.getDocument().addDocumentListener(new DocumentListener() {
@Override
public void insertUpdate(Docum...
MySQL “incorrect string value” error when save unicode string in Django
...f 255 and some kind of index on it (e.g. unique). Because utf8mb4 uses 33% more space than utf-8 you'll need to make these fields 33% smaller.
In this case, change the max_length from 255 to 191.
Alternatively you can edit your MySQL configuration to remove this restriction but not without some ...
How do I “Add Existing Item” an entire directory structure in Visual Studio?
...
|
show 7 more comments
548
...
How to create a self-signed certificate for a domain name for development?
...t for makecert.exe to be in my path. For the certificates I thought I'd be more secure and use -a SHA512 -len 8192 -- it took forever to generate. And as I suspected it might, it had zero impact on what level of encryption IIS used. By default IIS uses 128-bit, you have to do group policy stuff to c...
Difference between EXISTS and IN in SQL?
...e [field] in (1, 2, 3)
When you have a table in an in statement it makes more sense to use a join, but mostly it shouldn't matter. The query optimiser should return the same plan either way. In some implementations (mostly older, such as Microsoft SQL Server 2000) in queries will always get a nest...