大约有 48,000 项符合查询结果（耗时：0.0526秒） [XML]
Random record from MongoDB
I am looking to get a random record from a huge (100 million record) mongodb .
26 Answers
...
What is the difference between PS1 and PROMPT_COMMAND
...oc page: http://www.gnu.org/software/bash/manual/bashref.html
PROMPT_COMMAND
If set, the value is interpreted as a command to execute before
the printing of each primary prompt ($PS1).
I never used it, but I could have used this back when I only had sh.
...
Merging: Hg/Git vs. SVN
I often read that Hg (and Git and...) are better at merging than SVN but I have never seen practical examples of where Hg/Git can merge something where SVN fails (or where SVN needs manual intervention). Could you post a few step-by-step lists of branch/modify/commit/...-operations that show where S...
Getting the last element of a list
...
some_list[-1] is the shortest and most Pythonic.
In fact, you can do much more with this syntax. The some_list[-n] syntax gets the nth-to-last element. So some_list[-1] gets the last element, some_list[-2] gets the second to last, etc, all the way down t...
Difference between >>> and >>
What is the difference between >>> and >> operators in Java?
7 Answers
...
The located assembly's manifest definition does not match the assembly reference
...un some unit tests in a C# Windows Forms application (Visual Studio 2005), and I get the following error:
53 Answers
...
How to search by key=>value in a multidimensional array in PHP
..._r takes its fourth parameter by reference rather than by value; the ampersand & is crucial.
FYI: If you have an older version of PHP then you have to specify the pass-by-reference part in the call to search_r rather than in its declaration. That is, the last line becomes search_r($subarray, $k...
Given a number, find the next higher number which has the exact same set of digits as the original n
I just bombed an interview and made pretty much zero progress on my interview question. Can anyone let me know how to do this? I tried searching online but couldn't find anything:
...
How is this fibonacci-function memoized?
...mechanism in Haskell is by-need: when a value is needed, it is calculated, and kept ready in case it is asked for again. If we define some list, xs=[0..] and later ask for its 100th element, xs!!99, the 100th slot in the list gets "fleshed out", holding the number 99 now, ready for next access.
Th...
Unpacking, extended unpacking and nested extended unpacking
...lain with a few examples. Since you're talking about evaluating these "by hand," I'll suggest some simple substitution rules. Basically, you might find it easier to understand an expression if all the iterables are formatted in the same way.
For the purposes of unpacking only, the following substit...