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Select n random rows from SQL Server table
I've got a SQL Server table with about 50,000 rows in it. I want to select about 5,000 of those rows at random. I've thought of a complicated way, creating a temp table with a "random number" column, copying my table into that, looping through the temp table and updating each row with RAND() , and ...
How to pass objects to functions in C++?
...hich case you pass by non-const reference
the function should be callable without any argument, in which case you pass by pointer, so that users can pass NULL/0/nullptr instead; apply the previous rule to determine whether you should pass by a pointer to a const argument
they are of built-in types, ...
css 'pointer-events' property alternative for IE
I have a drop down navigation menu in which some of the title should not navigate to other page when clicked(these title open a drop down menu when clicked on) while others should navigate (these dont have dropdown and navigate directly).However, both types have href defined to them
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XAMPP - MySQL shutdown unexpectedly
When I open XAMPP and click start MySQL button and it gives me an error.
I had started it just before, but now it isn't working.
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What is the difference between active and passive FTP?
...eparate channels a nifty way of being able to send commands to the server without having to wait for the current data transfer to finish. As per the RFC, this is only mandated for a subset of commands, such as quitting, aborting the current transfer, and getting the status.
In active mode, the cl...
EXC_BAD_ACCESS signal received
When deploying the application to the device, the program will quit after a few cycles with the following error:
32 Answers...
Big-O summary for Java Collections Framework implementations? [closed]
I may be teaching a "Java crash-course" soon. While it is probably safe to assume that the audience members will know Big-O notation, it is probably not safe to assume that they will know what the order of the various operations on various collection implementations is.
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How do I style a dropdown with only CSS?
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Here are three solutions:
Solution #1 - appearance: none - with Internet Explorer 10 - 11 workaround (Demo)
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To hide the default arrow set appearance: none on the select element, then add your own custom arrow with background-image
select {
-webkit-appearance: none;
-moz-app...
How to return dictionary keys as a list in Python?
In Python 2.7 , I could get dictionary keys , values , or items as a list:
8 Answers
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How good is Java's UUID.randomUUID?
I know that randomized UUIDs have a very, very, very low probability for collision in theory, but I am wondering, in practice, how good Java's randomUUID() is in terms of not having collision? Does anybody have any experience to share?
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