大约有 30,000 项符合查询结果（耗时：0.0451秒） [XML]
Should MySQL have its timezone set to UTC?
...MySQL datetime fields and daylight savings time -- how do I reference the "extra" hour?
Converting negative values from FROM_UNIXTIME
Sources:
https://bugs.mysql.com/bug.php?id=68861
http://dev.mysql.com/doc/refman/5.0/en/date-and-time-functions.html
http://dev.mysql.com/doc/refman/5.1/en/dateti...
CROSS JOIN vs INNER JOIN in SQL
... but not vs CROSS JOIN. Intersection rows are in JOIN, left/right rows are extra (null-extended) rows in LEFT/RIGHT JOIN. It includes CROSS JOIN as a special case of (INNER) JOIN where there are no rows in the non-intersection.
– philipxy
Nov 29 '15 at 0:39
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可重入函数、不可重入函数及线程安全 - C/C++ - 清泛网 - 专注C/C++及内核技术
...
}
signal(SIGALRM,func);
alarm(1);
}
int main(int argc, char** argv)
{
signal(SIGALRM,func);
alarm(1);
for(;;)
{
if( ( ptr = getpwnam("sar") ) == NULL )
{
err_sys( "getpwnam error" );
}
}
return 0;
}
signal...
How do you get a list of the names of all files present in a directory in Node.js?
...s was the best solution for me as i wanted to specify filetype easier than string comparisons. Thanks.
– Pogrindis
Oct 26 '14 at 20:09
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html tables: thead vs th
... I didn't even know that th gets bolded by default, without extra CSS, thanks for that!
– CPHPython
Aug 10 '16 at 16:39
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sho...
Why should the “PIMPL” idiom be used? [duplicate]
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@Rob, I'm guessing there very little overhead to this. An extra class, but there is very little to them. Just a thin wrapper around the existing class. Someone correct me if I'm wrong, but the memory usage would just be an extra function table in RAM, a pointer to the pimpl and a re...
When should we call System.exit in Java
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In that case, it's not needed. No extra threads will have been started up, you're not changing the exit code (which defaults to 0) - basically it's pointless.
When the docs say the method never returns normally, it means the subsequent line of code is effect...
MySQL Conditional Insert
...t have dual already, you need to create it. CREATE TABLE dual ( dummy CHAR(1) DEFAULT 'x' NOT NULL CHECK (dummy = 'x') PRIMARY KEY ); INSERT INTO dual VALUES('x'); REVOKE ALL ON dual FROM PUBLIC; GRANT SELECT ON dual TO PUBLIC;
– Jonathan Leffler
Feb 24 '...
How do I remove the old history from a git repository?
...ow this is almost the same aswer as @yoyodin, but there are some important extra commands and informations here. I tried to edit the answer, but since it is a substantial change to @yoyodin's answer, my edit was rejected, so here's the information!
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When to Redis? When to MongoDB? [closed]
...lets you give it a key and look up a single value. Redis itself can store strings, lists, hashes, and a few other things; however, it only looks up by name.
Cache invalidation is one of computer science's hard problems; the other is naming things. That means you'll use Redis when you want to avoi...