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Simple way to transpose columns and rows in SQL?
...ate the list of items to UNPIVOT and PIVOT. This is then added to a query string to be executed. The plus of the dynamic version is if you have a changing list of colors and/or names this will generate the list at run-time.
All three queries will produce the same result:
| NAME | RED | GREEN | BL...
When should I use Lazy?
...erties for Name, PhoneNumber, and Orders. Name and PhoneNumber are regular strings but Orders is a navigation property that returns a list of every order the customer ever made.
You often might want to go through all your customer's and get their name and phone number to call them. This is a very q...
How to exclude certain directories/files from git grep search
... separate list $moved. I had issues with whitespace in
# the search-string, so this is loosely based on:
# http://www.linuxjournal.com/content/bash-preserving-whitespace-using-set-and-eval
x=1 ...
Creating JS object with Object.create(null)?
... in the map that you never inserted. For example, if you did a lookup on toString, you would find a function, even though you never put that value there. You can work around that like this:
if (Object.prototype.hasOwnProperty.call(p, 'toString')) {
// we actually inserted a 'toString' key into p...
What is uint_fast32_t and why should it be used instead of the regular int and uint32_t?
...ven addressable. In such a case working on them requires additional ops to extract the 32-bits from, say, 64-bit aligned units. See also the linked question. C++ standard is written so that it could work on a machine that has 37-bit words... so no 32-bit type there at all.
– Ya...
Are Java static calls more or less expensive than non-static calls?
...java.io.*;
class StaticVsInstanceBenchmark
{
public static void main( String[] args ) throws Exception
{
StaticVsInstanceBenchmark program = new StaticVsInstanceBenchmark();
program.run();
}
static final int DURATION = 1000;
public void run() throws Exception
...
When exactly are onSaveInstanceState() and onRestoreInstanceState() called?
...
String activityState;
@Override
public void onCreate(Bundle savedInstanceState) {
// call the super class onCreate to complete the creation of activity like
// the view hierarchy
super.onCreate(savedInstanceState);
// rec...
Is SHA-1 secure for password storage?
... that cost N once and can thereafter attack many passwords with very small extra cost per password.
If the pre-computed table is a rainbow table, then N can be somewhat bigger, because storage cost is reduced. The bottleneck on N becomes the CPU power that the attacker can muster, not the size of hi...
What are the differences between Pandas and NumPy+SciPy in Python? [closed]
... say that pandas is an alternative to Numpy and/or Scipy. Rather, it's an extra tool that provides a more streamlined way of working with numerical and tabular data in Python. You can use pandas data structures but freely draw on Numpy and Scipy functions to manipulate them.
...
Rails respond_with: how does it work?
...tion => posts_path)
# Note that if you want to pass a URL with a query string
# then the location option would be needed.
# /users?scope=active
respond_with(@user, :location => users_path(:scope => 'active'))
As an alternative, the responders gem not only provides some modules for over...