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Using LIMIT within GROUP BY to get N results per group?
...NCAT 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 ...
Set selected index of an Android RadioGroup
Is there a way to set the selected index of a RadioGroup in android, other than looping through the child radiobuttons and selecting checking the radio button at the selected index?
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YouTube API to fetch all videos on a channel
We need a video list by channel name of YouTube (using the API).
14 Answers
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How to execute a java .class from the command line
...ll Java that he should add . (current working directory) to the classpath, meaning the place where he is looking for code.
– Fredrik
Aug 14 '09 at 19:24
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Escape regex special characters in a Python string
... of Python 3.7 re.escape() was changed to escape only characters which are meaningful to regex operations.
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What is the difference between Amazon S3 and Amazon EC2 instance?
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Does it mean that S3, EBS are like hard disks which provide additional storage?
– Sangam254
Jan 18 '13 at 5:48
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Polymorphism in C++
...us ways:
When is the polymorphic type-specific code selected?
Run time means the compiler must generate code for all the types the program might handle while running, and at run-time the correct code is selected (virtual dispatch)
Compile time means the choice of type-specific code is made durin...
Python - List of unique dictionaries
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So make a temporary dict with the key being the id. This filters out the duplicates.
The values() of the dict will be the list
In Python2.7
>>> L=[
... {'id':1,'name':'john', 'age':34},
... {'id':1,'name':'john', 'age':34},
... {'id':2,'name':'hanna', 'age':30},...
Removing App ID from Developer Connection
How do I remove an App ID from the developer program portal area? I mistakenly added a couple of app id's under the wrong login and would like to remove them, but I am not seeing a way to do so.
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What is the volatile keyword useful for?
...he instance is set before the constructor has finished its execution. This means the method getInstance() returns an object that may not have been initialized completely. To make the code thread-safe, the keyword volatile can be used since Java 5 for the instance variable. Variables that are marked ...