大约有 40,000 项符合查询结果（耗时：0.0449秒） [XML]
When is it appropriate to use UDP instead of TCP? [closed]
...n you expect from a guy with a 2 digit rep? Nonetheless, I just now ran a test out of curiosity. The test read 1 million records (select * from sometable). I set the number of records to return with each individual client request to be 1, 10, and then 100 (three test runs with each protocol). Th...
How do I get currency exchange rates via an API such as Google Finance? [closed]
...les.org/alltableswithkeys][1]
Here is the YQL query builder, where you can test a query and copy the url: (NO LONGER AVAILABLE)
http://developer.yahoo.com/yql/console/?q=show%20tables&env=store://datatables.org/alltableswithkeys#h=select%20*%20from%20yahoo.finance.xchange%20where%20pair%20in%20%...
SQL join: selecting the last records in a one-to-many relationship
...
This is an example of the greatest-n-per-group problem that has appeared regularly on StackOverflow.
Here's how I usually recommend solving it:
SELECT c.*, p1.*
FROM customer c
JOIN purchase p1 ON (c.id = p1.customer_id)
LEFT OUTER JOIN purchase p2 ON (...
Do spurious wakeups in Java actually happen?
...
I read the post and gave me an idea about having unit tests for testing one application's conformance to the looping-wait paradigm by waking it up randomly/deterministically. Or is it already available somewhere?
– akarnokd
Jun 26 '09 at 19...
Constructors in JavaScript objects
...ctions
//------------------------------------------------------------
Fail.Test = function Fail_Test(){
A.Func.That.Does.Not.Exist();
}
Fail.Test();
</script>
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Best way to check if a URL is valid
...l('/'); // for my case https://www.xrepeater.com
$posted_url = "home";
// Test with one by one
/*$posted_url = "/home";
$posted_url = "xrepeater.com";
$posted_url = "www.xrepeater.com";
$posted_url = "http://www.xrepeater.com";
$posted_url = "https://www.xrepeater.com";
$posted_url = "https:/...
Get pandas.read_csv to read empty values as empty string instead of nan
...e it's missing this flag. For this example, you could use pandas.read_csv('test.csv',na_values=['nan'], keep_default_na=False).
– Michael Delgado
Sep 30 '15 at 20:17
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Java “user.dir” property - what exactly does it mean?
I want to use user.dir dir as a base dir for my unit tests (that creates a lot of files). Is it correct that this property points to the current working directory (e.g. set by the 'cd' command)?
...
How to change the background color of the options menu?
...round">@color/overflow_background</item>
...
</style>
Tested from API 4.2 to 5.0.
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Bash tool to get nth line from a file
...probably taken ~12 minutes.
mapfile
I have bash 3.1 and therefore cannot test the mapfile solution.
Conclusion
It looks like, for the most part, it's difficult to improve upon the head tail solution. At best the sed solution provides a ~3% increase in efficiency.
(percentages calculated with th...