大约有 16,000 项符合查询结果（耗时：0.0286秒） [XML]
When should I use C++ private inheritance?
Unlike protected inheritance, C++ private inheritance found its way into mainstream C++ development. However, I still haven't found a good use for it.
...
How to 'insert if not exists' in MySQL?
...
use INSERT IGNORE INTO table
see http://bogdan.org.ua/2007/10/18/mysql-insert-if-not-exists-syntax.html
there's also INSERT … ON DUPLICATE KEY UPDATE syntax, you can find explanations on dev.mysql.com
Post from bogdan.org.ua according t...
When increasing the size of VARCHAR column on a large table could there be any problems?
...
Another reason why you should avoid converting the column to varchar(max) is because you cannot create an index on a varchar(max) column.
share
|
improve this ...
What is the purpose of the “final” keyword in C++11 for functions?
...
Thanks! this is the point I was missing : ie that even your "leaf" classes need to mark their function as virtual even if they intend to override functions, and not to be overridden themselves
– lezebulon
Jan...
JavaScript: Check if mouse button down?
...garding Pax' solution: it doesn't work if user clicks more than one button intentionally or accidentally. Don't ask me how I know :-(.
The correct code should be like that:
var mouseDown = 0;
document.body.onmousedown = function() {
++mouseDown;
}
document.body.onmouseup = function() {
--mous...
How to know user has clicked “X” or the “Close” button?
...MMAND
public bool ClosedByXButtonOrAltF4 {get; private set;}
private const int SC_CLOSE = 0xF060;
private const int WM_SYSCOMMAND = 0x0112;
protected override void WndProc(ref Message msg)
{
if (msg.Msg == WM_SYSCOMMAND && msg.WParam.ToInt32() == SC_CLOSE)
ClosedByXButtonOrAltF4 ...
How does the Google “Did you mean?” Algorithm work?
...ords as trigrams or bigrams, so that when you are performing a lookup, you convert to n-gram, and lookup via hashtable or trie.
Use heuristics related to potential keyboard mistakes based on character location. So that "hwllo" should be "hello" because 'w' is close to 'e'.
Use a phonetic key (Sounde...
Hash function that produces short hashes?
...
If you don't need an algorithm that's strong against intentional modification, I've found an algorithm called adler32 that produces pretty short (~8 character) results. Choose it from the dropdown here to try it out:
http://www.sha1-online.com/
...
How to compare two dates?
...time(date1, "%d/%m/%Y") and newdate2 = time.strptime(date2, "%d/%m/%Y") to convert them to python's date format. Then, the comparison is obvious:
newdate1 > newdate2 will return False
newdate1 < newdate2 will return True
...
namedtuple and default values for optional keyword arguments
I'm trying to convert a longish hollow "data" class into a named tuple. My class currently looks like this:
21 Answers
...