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MySQL select 10 random rows from 600K rows fast
How can I best write a query that selects 10 rows randomly from a total of 600k?
26 Answers
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Why can't yield return appear inside a try block with a catch?
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I suspect this is a matter of practicality rather than feasibility. I suspect there are very, very few times where this restriction is actually an issue that can't be worked around - but the added complexity in the compiler would be very significant.
There are a few things like this ...
Unix command to find lines common in two files
... edited Jun 27 '17 at 9:58
Habeeb Perwad
6,1451212 gold badges7070 silver badges117117 bronze badges
answered Dec 17 '08 at 6:40
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JavaScript: Object Rename Key
Is there a clever (i.e. optimized) way to rename a key in a javascript object?
23 Answers
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Binary Data in MySQL [closed]
How do I store binary data in MySQL ?
9 Answers
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WAMP shows error 'MSVCR100.dll' is missing when install
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The MSVCR100.dll file is part of the Microsoft Visual C++, redistributables. You can install them and see if this solves your problem. After you install the above check if your wamp installation is correctly setup. Search for "my wamp icon stays orange" posts.
UPDATE 2019
Wampserver 3 r...
Sleeping in a batch file
When writing a batch file to automate something on a Windows box, I've needed to pause its execution for several seconds (usually in a test/wait loop, waiting for a process to start). At the time, the best solution I could find uses ping (I kid you not) to achieve the desired effect. I've found a be...
pip broke. how to fix DistributionNotFound error?
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I find this problem in my MacBook, the reason is because as @Stephan said, I use easy_install to install pip, and the mixture of both py package manage tools led to the pkg_resources.DistributionNotFound problem.
The resolve is:
easy_inst...
Is there a builtin identity function in python?
...ure was asked in issue 1673203 And from Raymond Hettinger said there won't be:
Better to let people write their own trivial pass-throughs
and think about the signature and time costs.
So a better way to do it is actually (a lambda avoids naming the function):
_ = lambda *args: args
advan...
Is gcc std::unordered_map implementation slow? If so - why?
We are developing a highly performance critical software in C++. There we need a concurrent hash map and implemented one. So we wrote a benchmark to figure out, how much slower our concurrent hash map is compared with std::unordered_map .
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