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Sqlite primary key on multiple columns
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@pratnala In standard SQL, yes. In SQLite, NULL is allowed in primary keys. This answer emphasizes that if you want more standard behavior, you need to add the NOT NULL yourself. My answer is just the very basic syntax for a multi-column pr...
How to sort an array based on the length of each element?
...: b.length - a.length
ES6 solution
Attention: not all browsers can understand ES6 code!
In ES6 we can use an arrow function expressions.
let array = ["ab", "abcdefgh", "abcd"];
array.sort((a, b) => b.length - a.length);
console.log(JSON.stringify(array, null, '\t'));
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What do I return if the return type of a method is Void? (Not void!)
... a function has to be Void?
Use return null. Void can't be instantiated and is merely a placeholder for the Class<T> type of void.
What's the point of Void?
As noted above, it's a placeholder. Void is what you'll get back if you, for example, use reflection to look at a method with a ...
Convert a row of a data frame to vector
...ate a vector out of a row of a data frame. But I don't want to have to row and column names. I tried several things... but had no luck.
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Command to get time in milliseconds
Is there a shell command in Linux to get the time in milliseconds?
12 Answers
12
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How to define a function in ghci across multiple lines?
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For guards (like your example), you can just put them all on one line and it works (guards do not care about spacing)
let abs n | n >= 0 = n | otherwise = -n
If you wanted to write your function with multiple definitions that pattern match on the arguments, like this:
fact 0 = 1
fact n =...
Specified argument was out of the range of valid values. Parameter name: site
... using IIS Express:
Open 'Add/Remove Programs' from the old control panel and run a repair on IIS Express
Or you might go Control Panel ->> Programs ->> Programs and Features ->> Turn Windows features on or off ->> Internet Information Services
and check the checkbox as show...
Search text in stored procedure in SQL Server
...t (within SProcs), instead use of "sys.procedures" worked for me. I understand that Microsoft recommends the use of information_schema, however apparently this is not working for many, hence Microsoft should look into this issue.
– Eddie Kumar
Sep 18 '17 at 11:...
DateTime to javascript date
...ptMilliseconds(DateTime); check in javascript (Press F12 in Google Chrome and go to console) var date = new Date(long); console.log(date.toString());
– Gonen09
Feb 3 at 15:11
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What's the role of adapters in Android?
I want to know when , where and how adapters are used in the context of Android.
10 Answers
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