大约有 42,000 项符合查询结果（耗时：0.0799秒） [XML]
must appear in the GROUP BY clause or be used in an aggregate function
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To workaround this issue, you must calculate the aggregate in a sub-query and then join it with itself to get the additional columns you'd need to show:
SELECT m.cname, m.wmname, t.mx
FROM (
SELECT cname, MAX(avg) AS mx
FROM makerar
GROUP BY cname
) t JOIN makerar m ON m.cname = t....
What does the restrict keyword mean in C++?
...zation, Christer Ericson says that while restrict is not part of the C++ standard yet, that it is supported by many compilers and he recommends it's usage when available:
restrict keyword
! New to 1999 ANSI/ISO C standard
! Not in C++ standard yet, but supported by many C++ comp...
How to unload a package without restarting R
...ating, but conceivably this could be used in a program to use one function and then another--although namespace referencing is probably a better idea for that use).
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Best JavaScript compressor [closed]
...t need any Node.js internals). It's a lot faster than both YUI Compressor and Google Closure, it compresses better than YUI on all scripts I tested it on, and it's safer than Closure (knows to deal with "eval" or "with").
Other than whitespace removal, UglifyJS also does the following:
changes l...
Encode String to UTF-8
I have a String with a "ñ" character and I have some problems with it. I need to encode this String to UTF-8 encoding. I have tried it by this way, but it doesn't work:
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Invert “if” statement to reduce nesting
... Probably just a matter of taste: I suggest changing the 2nd and 3rd "if" to "else if" to increase readability even more. If one overlooks the "return" statement it would still be clear that the following case is only checked if the previous one failed, i.e. that the order of the check...
Search All Fields In All Tables For A Specific Value (Oracle)
...an you not start with whatever client application is displaying this value and try to figure out what query it is using to obtain it?
Anyway, diciu's answer gives one method of generating SQL queries to check every column of every table for the value. You can also do similar stuff entirely in one ...
Script parameters in Bash
...arguments that you provide to a bashscript will appear in the variables $1 and $2 and $3 where the number refers to the argument. $0 is the command itself.
The arguments are seperated by spaces, so if you would provide the -from and -to in the command, they will end up in these variables too, so fo...
How to limit the amount of concurrent async I/O operations?
...can create delegate-bound tasks on the TPL that have not yet been started, and allow for a custom task scheduler to limit the concurrency. In fact, there's an MSDN sample for it here:
See also TaskScheduler .
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java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare();
I have an Android app running a thread. I want a Toast message to show with a message.
7 Answers
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