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what is the difference between GROUP BY and ORDER BY in sql
... returned.
GROUP BY will aggregate records by the specified columns which allows you to perform aggregation functions on non-grouped columns (such as SUM, COUNT, AVG, etc).
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How do I iterate through each element in an n-dimensional matrix in MATLAB?
...ar index for arrays in matlab is an important one. An array in MATLAB is really just a vector of elements, strung out in memory. MATLAB allows you to use either a row and column index, or a single linear index. For example,
A = magic(3)
A =
8 1 6
3 5 7
4 9 2
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How can I nullify css property?
Basically I have two external css in my page.
7 Answers
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how to solve “ruby installation is missing psych” error?
I used rvm to install ruby 1.9.3. even though it was successfully installed, it complained about libyaml. and now every time i wanna install a gem (say rails) this warning shows up:
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Java: how can I split an ArrayList in multiple small ArrayLists?
...ist are reflected in this list, and vice-versa. The returned list supports all of the optional list operations supported by this list.
Example:
List<Integer> numbers = new ArrayList<Integer>(
Arrays.asList(5,3,1,2,9,5,0,7)
);
List<Integer> head = numbers.subList(0, 4);
List...
Type List vs type ArrayList in Java [duplicate]
...tations of the List interface can be swapped. It seems that (1) is typically used in an application regardless of need (myself I always use this).
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How can I clear or empty a StringBuilder? [duplicate]
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Two ways that work:
Use stringBuilderObj.setLength(0).
Allocate a new one with new StringBuilder() instead of clearing the buffer.
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What's the difference between '$(this)' and 'this'?
... help to do DOM things just keep this in mind.
$(this)[0] === this
Basically every time you get a set of elements back jQuery turns it into a jQuery object. If you know you only have one result, it's going to be in the first element.
$("#myDiv")[0] === document.getElementById("myDiv");
And so ...
How do you disable viewport zooming on Mobile Safari?
I've tried all three of these to no avail:
15 Answers
15
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How to Iterate over a Set/HashSet without an Iterator?
...solution for me. I guess i have no choose, i must use Iterator. Thanks for all anyway.
– user1621988
Sep 17 '12 at 8:55
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