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COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
...T(field) or COUNT(*), and stick with it consistently, and if your database allows COUNT(tableHere) or COUNT(tableHere.*), use that.
In short, don't use COUNT(1) for anything. It's a one-trick pony, which rarely does what you want, and in those rare cases is equivalent to count(*)
Use count(*) fo...
Rebuild or regenerate 'ic_launcher.png' from images in Android Studio
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Beware using Asset Studio in Android Studio automatically adds padding, shrinking the resulting image.
– Androidcoder
Jun 16 '15 at 17:03
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Clone Object without reference javascript [duplicate]
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This is really very good reply. I got the exact solution for my problem. Thanks.
– Sumit Tawal
Jul 10 '15 at 12:26
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How do I find a stored procedure containing ?
... A million times what @PeteT said. This 4000 character limit really bit me a few years ago.
– Vivian River
Mar 31 '15 at 17:40
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Eclipse: The declared package does not match the expected package
...es of the project don't seem to be what Eclipse expects. The package names all have a prefix:
13 Answers
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Task vs Thread differences [duplicate]
I'm new to parallel programming. There are two classes available in .NET: Task and Thread .
4 Answers
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Ruby on Rails generates model field:type - what are the options for field:type?
...nother model's ID. I'd look it up myself, but I haven't figured out, among all my Ruby on Rails documentation links, how to find the definitive source.
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Responsive css background images
...ave defined a bg-image for the content) also responsive. Unfortunately I really don't have any idea on how to do this except for one thing that I can think of but it's quite a workaround. Creating multiple images and then using css screen size to change the images but I wanna know if there is a more...
What is a “cache-friendly” code?
...her end of the memory spectrum (DRAM), the memory is very cheap (i.e. literally millions of times cheaper) but takes hundreds of cycles after a request to receive the data. To bridge this gap between super fast and expensive and super slow and cheap are the cache memories, named L1, L2, L3 in decre...
Caveats of select/poll vs. epoll reactors in Twisted
...ePoll is a natural replacement for Select and Poll based networking, especially with Twisted. Which makes me paranoid, its pretty rare for a better technique or methodology not to come with a price.
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