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Count table rows
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Is it any faster when I use name of indexed column instead of * ? Like this: SELECT COUNT(id) FROM tablename
– user1810543
Nov 8 '12 at 21:01
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How does one capture a Mac's command key via JavaScript?
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EDIT: As of 2019, e.metaKey is supported on all major browsers as per the MDN.
Note that on Windows, although the ⊞ Windows key is considered to be the "meta" key, it is not going to be captured by browsers as such.
This is...
How to customize ?
Is it possible to change the appearance of <input type="file"> ?
18 Answers
18...
Can I change the root EBS device of my amazon EC2 instance?
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Yep, it's dead easy:
Stop the instance.
Detach the root EBS volume.
Attach the alternate EBS volume as the root: /dev/sda1
Start the instance.
This presupposes that your alternate EBS volume is bootable, of course - it has to ...
Download file of any type in Asp.Net MVC using FileResult?
I've had it suggested to me that I should use FileResult to allow users to download files from my Asp.Net MVC application. But the only examples of this I can find always has to do with image files (specifying content type image/jpeg).
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Tools for analyzing performance of a Haskell program
...t of Real World Haskell.
GC Statistics
Firstly, ensure you're compiling with ghc -O2. And you might make sure it is a modern GHC (e.g. GHC 6.12.x)
The first thing we can do is check that garbage collection isn't the problem.
Run your program with +RTS -s
$ time ./A +RTS -s
./A +RTS -s
749700
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How to set -source 1.7 in Android Studio and Gradle
... 19. You can now use features like the diamond operator, multi-catch, try-with-resources, strings in switches, etc. Add the following to your build.gradle.
android {
compileSdkVersion 19
buildToolsVersion "19.0.0"
defaultConfig {
minSdkVersion 7
targetSdkVersion 19
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throw new std::exception vs throw std::exception
...to throw and catch exceptions is to throw an exception object and to catch it by reference (usually const reference). The C++ language requires the compiler to generate the appropriate code to construct the exception object and to properly clean it up at the appropriate time.
Throwing a pointer to ...
A Space between Inline-Block List Items [duplicate]
Why do the inline-block list items have a space in them? No matter how I make my list items into a menu, I always get spaces.
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Broken references in Virtualenvs
I recently installed a bunch of dotfiles on my Mac along with some other applications (I changed to iTerm instead of Terminal, and Sublime as my default text editor) but ever since, all my virtual environments have stopped working, although their folders inside .virtualenvs are still there and they ...