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How to do a FULL OUTER JOIN in MySQL?

... syntax. According to MySql's outer join simplification, the right join is converted to the equivalent left join by switching the t1 and t2 in the FROM and ON clause in the query. Thus, the MySql Query Optimizer translates the original query into the following - SELECT * FROM t1 LEFT JOIN t2 ON t1...
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Check if application is on its first run [duplicate]

I am new to android development and and I want to setup some of application's attributes based on Application first run after installation. Is there any way to find that the application is running for the first time and then to setup its first run attributes? ...
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What's the difference between --general-numeric-sort and --numeric-sort options in gnu sort

...l-numeric’ Sort numerically, using the standard C function strtod to convert a prefix of each line to a double-precision floating point number. This allows floating point numbers to be specified in scientific notation, like 1.0e-34 and 10e100. The LC_NUMERIC locale determines the d...
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Why does “return list.sort()” return None, not the list?

... l = sorted(l.append('2')) (I just added semi-colon so you could cut/paste and run) – JGFMK May 30 '18 at 9:54 ...
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How do you disable the unused variable warnings coming out of gcc in 3rd party code I do not wish to

... off unused variable warnings? I'm getting errors out of boost on windows and I do not want to touch the boost code: 9 Ans...
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What happens when a duplicate key is put into a HashMap?

...e times to HashMap ’s put method, what happens to the original value? And what if even the value repeats? I didn’t find any documentation on this. ...
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Round a double to 2 decimal places [duplicate]

... too. So, use this instead (Adapted from this answer by Louis Wasserman and this one by Sean Owen.) public static double round(double value, int places) { if (places < 0) throw new IllegalArgumentException(); BigDecimal bd = BigDecimal.valueOf(value); bd = bd.setScale(places, Rou...
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How to play with Control.Monad.Writer in haskell?

I'm new to functional programming and recently learning at Learn You a Haskell , but when I went through this chapter , I got stuck with the program below: ...
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How to detect the currently pressed key?

...u haven't answered the question properly. The OP is asking about all keys and used the Shift key as an example only. So how do you detect other keys such as A to Z, 0 to 9 etc. – Ash Dec 18 '09 at 10:03 ...
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What is the significance of 1/1/1753 in SQL Server?

...se the Gregorian Calendar. So with the greater range of datetime2 SELECT CONVERT(VARCHAR, DATEADD(DAY,-5,CAST('1752-09-13' AS DATETIME2)),100) Returns Sep 8 1752 12:00AM One final point with the datetime2 data type is that it uses the proleptic Gregorian calendar projected backwards to well ...