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Efficiently convert rows to columns in sql server
... for ColumnName in (' + @cols + N')
) p '
exec sp_executesql @query;
See Demo.
Using an aggregate function
If you do not want to use the PIVOT function, then you can use an aggregate function with a CASE expression:
select
max(case when columnname = 'FirstName' then ...
CSS: background image on background color
...nswered Jan 15 '18 at 17:12
Risa__BRisa__B
39544 silver badges88 bronze badges
...
Putting git hooks into repository
...sh
if [ -x $0.local ]; then
$0.local "$@" || exit $?
fi
if [ -x tracked_hooks/$(basename $0) ]; then
tracked_hooks/$(basename $0) "$@" || exit $?
fi
The installation script would move all pre-existing hooks to the side (append .local to their names), and symlink all known hook names to the...
Converting strings to floats in a DataFrame
...
NOTE: pd.convert_objects has now been deprecated. You should use pd.Series.astype(float) or pd.to_numeric as described in other
answers.
This is available in 0.11. Forces conversion (or set's to nan)
This will work even when astype will ...
Mixin vs inheritance
...dited Jun 21 at 11:36
underscore_d
4,91633 gold badges2828 silver badges5454 bronze badges
answered May 13 '09 at 20:42
...
Do zombies exist … in .NET?
...g a thread can cause problems:
class Program
{
static readonly object _lock = new object();
static void Main(string[] args)
{
Thread thread = new Thread(new ThreadStart(Zombie));
thread.Start();
Thread.Sleep(500);
thread.Abort();
Monitor.Enter(_...
Pagination in a REST web application
... Range header also works to declare an order:
Range: products-by-date=2009_03_27-
to get all products newer than that date or
Range: products-by-date=0-2009_11_30
to get all products older than that date. '0' is probably not best solution, but RFC seems to want something for range start. There...
How to sort an array by a date property
...(a.date);
});
More Generic Answer
array.sort(function(o1,o2){
if (sort_o1_before_o2) return -1;
else if(sort_o1_after_o2) return 1;
else return 0;
});
Or more tersely:
array.sort(function(o1,o2){
return sort_o1_before_o2 ? -1 : sort_o1_after_o2 ? 1 : 0;
});
...
Advantage of creating a generic repository vs. specific repository for each object?
...
public abstract class Repository<TEntity>
{
private DataContext _dataContext;
protected Repository(DataContext dataContext)
{
_dataContext = dataContext;
}
protected IQueryable<TEntity> Query
{
get { return _dataContext.GetTable<TEntity>()...
How to structure a express.js application?
...js
|~models
| |-monkey.js
| |-zoo.js
|~views
| |~zoos
| |-new.jade
| |-_form.jade
|~test
| |~controllers
| |-zoo.js
| |~models
| |-zoo.js
|-index.js
I use Exports to return what's relevant. For instance, in the models I do:
module.exports = mongoose.model('PhoneNumber', PhoneNumberSchem...