大约有 48,000 项符合查询结果（耗时：0.0660秒） [XML]
Python class inherits object
...problem…
Python introduced new-style classes back in Python 2.2, and by now old-style classes are really quite old. Discussion of old-style classes is buried in the 2.x docs, and non-existent in the 3.x docs.
The problem is, the syntax for old-style classes in Python 2.x is the same as the alter...
SET versus SELECT when assigning variables?
...d hide the fact that multiple values were returned (so you'd likely never know why something was going wrong elsewhere - have fun troubleshooting that one)
When assigning from a query if there is no value returned then SET will assign NULL, where SELECT will not make the assignment at all (so the ...
How can I use threading in Python?
...nction are provided by two libraries:multiprocessing, and also its little known, but equally fantastic step child:multiprocessing.dummy.
multiprocessing.dummy is exactly the same as multiprocessing module, but uses threads instead (an important distinction - use multiple processes for CPU-intensive...
Efficiently convert rows to columns in sql server
...nt, PostalCode, LastName, AccountNumber)
) piv;
See Demo.
Pivot with unknown number of columnnames
If you have an unknown number of columnnames that you want to transpose, then you can use dynamic SQL:
DECLARE @cols AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX)
select @cols = STUFF((SELECT ',...
Which Architecture patterns are used on Android? [closed]
I'm doing a small research of mobile platforms and I would like to know which design patterns are used in Android?
12 Answe...
Suggestions for debugging print stylesheets?
...s should do the trick.
Update: The menus have changed in DevTools.
It can now be found by clicking on the "three-dots" menu in the top right corner > More Tools > Rendering Settings > Emulate media > print.
Source: Google DevTools page*
...
What is java interface equivalent in Ruby?
...ple: where in java.util.Set<E> does it actually say that it is, you know, a set? Nowhere! Or more precisely, in the documentation. In English.
In pretty much all cases of interfaces, both from Java and .NET, all the relevant information is actually in the docs, not in the types. So, if the typ...
Named regular expression group “(?Pregexp)”: what does “P” stand for?
...Perl 5; O'Reilly
publishes books about both languages.)
As you may know, Python 1.5 adds a new regular expression module that
more closely matches Perl's syntax. We've tried to be as close to the
Perl syntax as possible within Python's syntax. However, the regex
syntax has some Python...
Fastest exit strategy for a Panic Button in Crisis/Abuse Websites? [closed]
... to that page, click the button, visit another page, then hit back, you're now on 54.186.79.95/decoywebsite and there's no record of you being on 54.186.79.95/, if cache is disabled, your server will see the "../decoywebsite" request and send a decoy page. Unfortunately, you can't modify the entire ...
What algorithm can be used for packing rectangles of different sizes into the smallest rectangle pos
... I was just playing with something like that on a bit of paper, right now looks fairly optimal in most cases, even without rotating the rectangles or anything
– Fire Lancer
Jul 31 '09 at 16:37
...