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selecting unique values from a column
... if you have multiple duplicate results as a result of a JOIN you can do a GROUP BY and get the full results filtered.
– Chadwick Meyer
Dec 10 '15 at 19:55
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Converting JSON data to Java object
...avaBean class.
You have a JSON object with several properties of which the groups property represents an array of nested objects of the very same type. This can be parsed with Gson the following way:
package com.stackoverflow.q1688099;
import java.util.List;
import com.google.gson.Gson;
public cla...
Why are ToLookup and GroupBy different?
... ILookup<TKey, TSource> also implements interface IEnumerable<IGrouping<TKey, TSource>> .
3 Answers
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Unable to open project… cannot be opened because the project file cannot be parsed
...anges from both branches after a merge.
I had a merge conflict in the PBXGroup section (whose beginning is indicated by a block comment like this: /* Begin PBXGroup section */) of the project.pbxproj file. However, the problem I encountered can occur in other places in the project.pbxproj file as ...
Converting a Pandas GroupBy output from Series to DataFrame
... 1 1
Or something like:
In [36]: DataFrame({'count' : df1.groupby( [ "Name", "City"] ).size()}).reset_index()
Out[36]:
Name City count
0 Alice Seattle 1
1 Bob Seattle 2
2 Mallory Portland 2
3 Mallory Seattle 1
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Create a dictionary on a list with grouping
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var groupedDemoClasses = (from demoClass in mySepcialVariableWhichIsAListOfDemoClass
group demoClass by demoClass.GroupKey
into groupedDemoClass
select...
How can I render a list select box (dropdown) with bootstrap?
....click(function(){
var selText = $(this).text();
$(this).parents('.btn-group').find('.dropdown-toggle').html(selText+' <span class="caret"></span>');
});
http://www.bootply.com/b4NKREUPkN
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How to create a directory using Ansible
...correct, but some consider it a best practice to explicitly declare owner, group and mode. One of the reasons to do this - even when it seems unnecessary - is because over time your current assumptions fail: a distro/release changes and with it come different umask defaults, or ticket databases can ...
RegEx to exclude a specific string constant [duplicate]
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In .NET you can use grouping to your advantage like this:
http://regexhero.net/tester/?id=65b32601-2326-4ece-912b-6dcefd883f31
You'll notice that:
(ABC)|(.)
Will grab everything except ABC in the 2nd group. Parenthesis surround each group....
How can I remove duplicate rows?
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Assuming no nulls, you GROUP BY the unique columns, and SELECT the MIN (or MAX) RowId as the row to keep. Then, just delete everything that didn't have a row id:
DELETE FROM MyTable
LEFT OUTER JOIN (
SELECT MIN(RowId) as RowId, Col1, Col2, Col3...