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Using LIMIT within GROUP BY to get N results per group?
..._CONCAT aggregated function to get all years into a single column, grouped by id and ordered by rate:
SELECT id, GROUP_CONCAT(year ORDER BY rate DESC) grouped_year
FROM yourtable
GROUP BY id
Result:
-----------------------------------------------------------
| ID | GROUPED_YEAR ...
Simple way to create matrix of random numbers
I am trying to create a matrix of random numbers, but my solution is too long and looks ugly
13 Answers
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How do I get a platform-dependent new line character?
...) you can use %n as in
Calendar c = ...;
String s = String.format("Duke's Birthday: %1$tm %1$te,%1$tY%n", c);
//Note `%n` at end of line ^^
String s2 = String.format("Use %%n as a platform independent newline.%n");
// %% becomes % ^^
// ...
in javascript, how can i get the last character in a string [duplicate]
If I have the following variable in javascript
7 Answers
7
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Why are C# 3.0 object initializer constructor parentheses optional?
It seems that the C# 3.0 object initializer syntax allows one to exclude the open/close pair of parentheses in the constructor when there is a parameterless constructor existing. Example:
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Adding a UILabel to a UIToolbar
I'm trying to add a label to my toolbar. Button works great, however when I add the label object, it crashes. Any ideas?
8 ...
What's the difference between the data structure Tree and Graph?
Academically speaking, what's the essential difference between the data structure Tree and Graph? And how about the tree based search and Graph based search?
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Convert a 1D array to a 2D array in numpy
I want to convert a 1-dimensional array into a 2-dimensional array by specifying the number of columns in the 2D array. Something that would work like this:
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What rules does Pandas use to generate a view vs a copy?
I'm confused about the rules Pandas uses when deciding that a selection from a dataframe is a copy of the original dataframe, or a view on the original.
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Rebasing a Git merge commit
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There are two options here.
One is to do an interactive rebase and edit the merge commit, redo the merge manually and continue the rebase.
Another is to use the --rebase-merges option on git rebase, which is described as follows from the manual:
By default, a rebase will simply dro...