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How to randomly select an item from a list?

...ults, but depending on the start seed, it's not guaranteed. If you want to select n distinct random elements from a list lst, use random.sample(lst, n) – Graham Dec 23 '18 at 17:02 ...
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How do I make a placeholder for a 'select' box?

...s which is working out just fine. But I'd like to use a placeholder for my selectboxes as well. Of course I can just use this code: ...
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How to declare a variable in a PostgreSQL query

...ows you to return a table of temporary values. WITH master_user AS ( SELECT login, registration_date FROM users WHERE ... ) SELECT * FROM users WHERE master_login = (SELECT login FROM master_user) AND (SELECT registration_date FROM ma...
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Select first row in each GROUP BY group?

As the title suggests, I'd like to select the first row of each set of rows grouped with a GROUP BY . 17 Answers ...
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How to concatenate text from multiple rows into a single text string in SQL server?

...y, John, Sam 2 Alaina, Edward I used the following T-SQL: SELECT Main.SubjectID, LEFT(Main.Students,Len(Main.Students)-1) As "Students" FROM ( SELECT DISTINCT ST2.SubjectID, ( SELECT ST1.StudentName + ',' AS [text()] FR...
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How can I use the $index inside a ng-repeat to enable a class and show a DIV?

... The issue here is that ng-repeat creates its own scope, so when you do selected=$index it creates a new a selected property in that scope rather than altering the existing one. To fix this you have two options: Change the selected property to a non-primitive (ie object or array, which makes jav...
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Insertion Sort vs. Selection Sort

I am trying to understand the differences between Insertion Sort and Selection Sort. 20 Answers ...
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Select count(*) from multiple tables

How can I select count(*) from two different tables (call them tab1 and tab2 ) having as result: 18 Answers ...
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Is there a way to make a DIV unselectable?

... I wrote a simple jQuery extension to disable selection some time back: Disabling Selection in jQuery. You can invoke it through $('.button').disableSelection(); Alternately, using CSS (cross-browser): .button { user-select: none; -moz-user-select: none...
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jQuery get value of selected radio button

The problem statement is simple. I need to see if user has selected a radio button from a radio group. Every radio button in the group share same id. ...