大约有 44,000 项符合查询结果（耗时：0.0613秒） [XML]
SQL select only rows with max value on a column [duplicate]
...
I know that MySQL allows you to add non aggregate fields to a "grouped by" query, but I find that kinda pointless. Try running this select id, max(rev), rev from YourTable group by id and you see what I mean. Take your time and ...
Awaiting multiple Tasks with different results
...eTask;
var car = await carTask;
You can also use Task.Result (since you know by this point they have all completed successfully). However, I recommend using await because it's clearly correct, while Result can cause problems in other scenarios.
...
Is System.nanoTime() completely useless?
...s System.nanoTime() returns the time value using a CPU specific counter. Now consider the following case I use to measure time of a call:
...
Can you change what a symlink points to after it is created?
... alternately.
Editor's note: This is how Capistrano has done it for years now, ever since ~2.15. See this pull request.
share
|
improve this answer
|
follow
|...
How is a CRC32 checksum calculated?
... x^5 + x^4 + 3*x^3 + x^2 + x^1 + x^0 (or that original number we had)
I know this is a leap of faith but this is beyond my capability as a line-programmer. If you are a hard-core CS-student or engineer I challenge to break this down. Everyone will benefit from this analysis.
So to work out a full...
Can I incorporate both SignalR and a RESTful API?
...
@davids.s: I know, that I'm a little late, but thanks for the link. I've added an excerpt for further readers.
– Dennis
Aug 21 '15 at 7:18
...
Is there a way to “autosign” commits in Git with a GPG key?
...to make sure your commits are signed, there is a proposal (branch 'pu' for now, December 2013, so no guarantee it will make it to a git release) to add a config which will take care of that option for you.
Update May 2014: it is in Git 2.0 (after being resend in this patch series)
See commit 2af2ef...
Can you list the keyword arguments a function receives?
...argspec(func)
(['a', 'b', 'c'], 'args', 'kwargs', (42,))
If you want to know if its callable with a particular set of args, you need the args without a default already specified. These can be got by:
def getRequiredArgs(func):
args, varargs, varkw, defaults = inspect.getargspec(func)
if ...
Tool to convert Python code to be PEP8 compliant
I know there are tools which validate whether your Python code is compliant with PEP8, for example there is both an online service and a python module .
...
Task not serializable: java.io.NotSerializableException when calling function outside closure only o
...e Serialisable interface, so this is not what's causing your task to fail. Now this doesn't mean that you can serialise an RDD with Spark and avoid NotSerializableException
Spark is a distributed computing engine and its main abstraction is a resilient distributed dataset (RDD), which can be viewed...