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How to use GROUP_CONCAT in a CONCAT in MySQL
...what you need.
Update
Splitting in two steps. First we get a table having all values(comma separated) against a unique[Name,id]. Then from obtained table we get all names and values as a single value against each unique id
See this explained here SQL Fiddle Demo (scroll down as it has two result se...
Maven 3 warnings about build.plugins.plugin.version
...ople have mentioned why the issue is happening, but fail to suggest a fix. All I needed to do was to go into my POM file for my project, and add the <version> tag as shown above.
To discover the version number, one way is to look in Maven's output after it finishes running. Where you are miss...
performing HTTP requests with cURL (using PROXY)
I have this proxy address: 125.119.175.48:8909
16 Answers
16
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Structs in Javascript
...a retyping is still an issue, as there are more jumps than copying the new ___ ( , , , ) archetype. Also, there is no readability. Once you get used to coding, new READABLE_PART(ignore everything in here) becomes very scannable and self documenting, as opposed to {read: "ignore", everything: "igno...
Lombok added but getters and setters not recognized in Intellij IDEA
...sing IntelliJ IDEA on ubuntu. I added lombok.jar into my project and installed the Lombok plugin for IDEA. I have access to the annotations but the getters and setters aren't generated. I get the same errors I would get if I tried accessing a getter or setter method that doesn't exist. What co...
How to go to a specific element on page? [duplicate]
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+1 for the native scrollIntoView which i didnt know at all. for a moment i thought it was jquery. :)
– naveen
Jan 26 '11 at 6:15
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Automatically expanding an R factor into a collection of 1/0 indicator variables for every factor le
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And if you want to convert all factor columns, you can use: model.matrix(~., data=iris)[,-1]
– user890739
Jan 5 '16 at 0:32
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How can I write output from a unit test?
Any call in my unit tests to either Debug.Write(line) or Console.Write(Line) simply gets skipped over while debugging and the output is never printed. Calls to these functions from within classes I'm using work fine.
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Sort rows in data.table in decreasing order on string key `order(-x,v)` gives error on data.table 1.
...d the following answer is no longer necessary.
You can use DT[order(-rank(x), y)].
x y v
1: c 1 7
2: c 3 8
3: c 6 9
4: b 1 1
5: b 3 2
6: b 6 3
7: a 1 4
8: a 3 5
9: a 6 6
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how to check if object already exists in a list
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It depends on the needs of the specific situation. For example, the dictionary approach would be quite good assuming:
The list is relatively stable (not a lot of inserts/deletions, which dictionaries are not optimized for)
The list is quite large (otherwise the overhead of the di...