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The cast to value type 'Int32' failed because the materialized value is null
...where there can be unexpected nulls in different places. ...DefaultIfEmpty(0).Sum(0) can help in this (quite simple) case, where there might be no elements and sql's SUM returns null whereas c# expect 0.
A more general approach is to use ?? which will be translated to COALESCE whenever there is a r...
How can I pad an int with leading zeros when using cout
...to output an int with leading zeros, so the value 1 would be printed as 001 and the value 25 printed as 025 . How can I do this?
...
AddBusinessDays and GetBusinessDays
...atic DateTime AddBusinessDays(DateTime date, int days)
{
if (days < 0)
{
throw new ArgumentException("days cannot be negative", "days");
}
if (days == 0) return date;
if (date.DayOfWeek == DayOfWeek.Saturday)
{
date = date.AddDays(2);
days -= 1;
...
Efficiently updating database using SQLAlchemy ORM
...on on commit you don't have any stale data issues.
In the almost-released 0.5 series you could also use this method for updating:
session.query(Stuff).update({Stuff.foo: Stuff.foo + 1})
session.commit()
That will basically run the same SQL statement as the previous snippet, but also select the c...
What is the javascript filename naming convention? [closed]
...
190
One possible naming convention is to use something similar to the naming scheme jQuery uses. It'...
Flatten an irregular list of lists
...
390
Using generator functions can make your example a little easier to read and probably boost the p...
Get url parameters from a string in .NET
...m1");
Check documentation at http://msdn.microsoft.com/en-us/library/ms150046.aspx
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Remove 'a' from legend when using aesthetics and geom_text
... FALSE)
The argument show_guide changed name to show.legend in ggplot2 2.0.0 (see release news).
Pre-ggplot2 2.0.0:
With show_guide = FALSE like so...
ggplot( data=iris, aes(x=Sepal.Length, y=Sepal.Width , colour = Species , shape = Species, label = Species ) , size=20 ) +
geom_point()+
geom...
Get all git commits since last tag
...ndows you could do
for /f "delims=" %a in ('git describe --tags --abbrev^=0') do @set latesttag=%a
git log %latesttag%..HEAD --oneline
and on linux / git bash / windows bash
git log $(git describe --tags --abbrev=0)..HEAD --oneline
Also, if you have a case where you know a tag in history and w...
Obtain Bundle Identifier programmatically
...2
let bundleIdentifier = NSBundle.mainBundle().bundleIdentifier
Swift 3.0
let bundleIdentifier = Bundle.main.bundleIdentifier
Xamarin.iOS
var bundleIdentifier = NSBundle.MainBundle.BundleIdentifier
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