大约有 40,000 项符合查询结果（耗时：0.0461秒） [XML]
Does MySQL index foreign key columns automatically?
...million records. This is ofc MySQL 5.1 InnoDB. The table has three fields, one is primary key integer, the other is already indexed. The third was a foreign key to primary key of another table. Without adding an explicit index, lookups took several seconds here. Show index from table also didn't sho...
Does using “new” on a struct allocate it on the heap or stack?
...here value type variables are allocated. That's a different question - and one to which the answer isn't just "on the stack". It's more complicated than that (and made even more complicated by C# 2). I have an article on the topic and will expand on it if requested, but let's deal with just the new ...
What is the difference between a reference type and value type in c#?
...ferent pieces of paper containing the same directions to my house - and if one person followed those directions and painted my house red, then the second person would see that change too. If they both just had separate pictures of my house on the paper, then one person colouring their paper wouldn't...
What is the difference between supervised learning and unsupervised learning? [closed]
...d, which means that your examples must be labeled, or explicitly say which ones are faces and which ones aren't.
In an unsupervised algorithm your examples are not labeled, i.e. you don't say anything. Of course, in such a case the algorithm itself cannot "invent" what a face is, but it can try to ...
Get/pick an image from Android's built-in Gallery app programmatically
... return uri.getPath();
}
}
Selecting Multiple Pictures
Since someone requested that information in a comment and it's better to have information gathered.
Set an extra parameter EXTRA_ALLOW_MULTIPLE on the intent:
intent.putExtra(Intent.EXTRA_ALLOW_MULTIPLE, true);
And in the Result ha...
When would you use the different git merge strategies?
...e is the default for non-fast-forward merges. We're all familiar with that one.
Octopus
I've used octopus when I've had several trees that needed to be merged. You see this in larger projects where many branches have had independent development and it's all ready to come together into a single he...
List passed by ref - help me explain this behaviour
...ed myList.Sort();
Finally, when you did: myList' = myList2, you lost the one of the reference but not the original and the collection stayed sorted.
If you use by reference (ref) then myList' and myList will become the same (only one reference).
Note: I use myList' to represent the parameter t...
Going from a framework to no-framework [closed]
...nst cross-site request forgery, but I'm sure Google can help you with that one. The OWASP Security Cheatsheets include a section on it if you want to implement your own protection.
Out of curiosity, I decided to also start looking at standalone components and here's what I've found so far:
Templat...
Hashing a dictionary?
...he body of the question, the answer is complete.)
Nested Dictionaries
If one searches Stack Overflow for how to hash a dictionary, one might stumble upon this aptly titled question, and leave unsatisfied if one is attempting to hash multiply nested dictionaries. The answer above won't work in thi...
How to force use of overflow menu on devices with menu button
...enu items that don't fit into the ActionBar go into the overflow menu (the one that is reached from the Action Bar not the menu button) even on devices that do have a Menu button . This seems much more intuitive for users than throwing them into a separate menu list that requires the user to jump ...