大约有 42,000 项符合查询结果（耗时：0.0875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....
Default parameters with C++ constructors [closed]
...efault parameters, so long as the parameters make sense. Classes in the standard use them as well, which speaks in their favor.
One thing to watch out for is if you have defaults for all but one parameter, your class can be implicitly converted from that parameter type. Check out this thread for ...
What is the best way to tell if a character is a letter or number in Java without using regexes?
What is the best and/or easiest way to recognize if a string.charAt(index) is an A-z letter or a number in Java without using regular expressions? Thanks.
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How to determine height of UICollectionView with FlowLayout
I've got an UICollectionView with an UICollectionViewFlowLayout , and i want to calculate its content size (for return in intrinsicContentSize needed for adjusting its height via AutoLayout).
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virtualenvwrapper and Python 3
I installed python 3.3.1 on ubuntu lucid and successfully created a virtualenv as below
9 Answers
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how to make a whole row in a table clickable as a link?
I'm using Bootstrap and the following doesn't work:
26 Answers
26
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How do you track record relations in NoSQL?
I am trying to figure out the equivalent of foreign keys and indexes in NoSQL KVP or Document databases. Since there are no pivotal tables (to add keys marking a relation between two objects) I am really stumped as to how you would be able to retrieve data in a way that would be useful for normal we...
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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C# 'is' operator performance
... answered Mar 26 '09 at 16:09
Andrew HareAndrew Hare
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How can I use numpy.correlate to do autocorrelation?
I need to do auto-correlation of a set of numbers, which as I understand it is just the correlation of the set with itself.
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