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What are the use cases for selecting CHAR over VARCHAR in SQL?
I realize that CHAR is recommended if all my values are fixed-width. But, so what? Why not just pick VARCHAR for all text fields just to be safe.
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What is the Haskell response to Node.js?
...f Node.js as it does non-blocking I/O natively and has ways to scale deployments easily to more than one processor (something not even built-in in Node.js). More details at http://journal.dedasys.com/2010/04/29/erlang-vs-node-js and Node.js or Erlang
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Pass a data.frame column name to a function
I'm trying to write a function to accept a data.frame ( x ) and a column from it. The function performs some calculations on x and later returns another data.frame. I'm stuck on the best-practices method to pass the column name to the function.
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What's the difference between using “let” and “var”?
...ce is scoping rules. Variables declared by var keyword are scoped to the immediate function body (hence the function scope) while let variables are scoped to the immediate enclosing block denoted by { } (hence the block scope).
function run() {
var foo = "Foo";
let bar = "Bar";
console.log(f...
What use is find_package() if you need to specify CMAKE_MODULE_PATH anyway?
...Module mode
Find<package>.cmake file located within your project. Something like this:
CMakeLists.txt
cmake/FindFoo.cmake
cmake/FindBoo.cmake
CMakeLists.txt content:
list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}/cmake")
find_package(Foo REQUIRED) # FOO_INCLUDE_DIR, FOO_LIBRARIE...
What should I use Android AccountManager for?
...s a convenient way to share data across applications
Note: there are other methods of inter-process communication on Android.
ContentProvider schedules the database access in a background thread The AsyncQueryHanlder helps to query the ContentProvider in a background thread, preventing Application N...
Local Storage vs Cookies
I want to reduce load times on my websites by moving all cookies into local storage since they seem to have the same functionality. Are there any pros/cons (especially performance-wise) in using local storage to replace cookie functionality except for the obvious compatibility issues?
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What is the purpose of Rank2Types?
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Do not functions in Haskell already support polymorphic arguments?
They do, but only of rank 1. This means that while you can write a function that takes different types of arguments without this extension, you can't write a function that uses its argument as different types in the ...
Why use pointers? [closed]
I know this is a really basic question, but I've just started with some basic C++ programming after coding a few projects with high-level languages.
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In HTML5, should the main navigation be inside or outside the element?
... be used either inside or outside the page's masthead <header> element. For websites having both secondary and main navigation, it seems common to include the secondary navigation as a <nav> element inside the masthead <header> element with the main navigation as a <nav&...