大约有 19,000 项符合查询结果（耗时：0.0252秒） [XML]
Entity Framework. Delete all rows in table
...or some similar situation.
Either
The amount of data is small or
The performance doesn't matter
Simply call:
VotingContext.Votes.RemoveRange(VotingContext.Votes);
Assuming this context:
public class VotingContext : DbContext
{
public DbSet<Vote> Votes{get;set;}
public DbSe...
Shell command to tar directory excluding certain files/folders
...
The ordering of parameters seems to matter and this form works for me.
– cstamas
Oct 1 '18 at 12:33
1
...
How set the default repository
...xchange.using('gps', function() { StackExchange.gps.track('embedded_signup_form.view', { location: 'question_page' }); });
$window.unbind('scroll', onScroll);
}
};
...
return query based on date
...fter a given date:
db.gpsdatas.find({"createdAt" : { $gte : new ISODate("2012-01-12T20:15:31Z") }});
I'm using $gte (greater than or equals), because this is often used for date-only queries, where the time component is 00:00:00.
If you really want to find a date that equals another date, the sy...
What's the difference between commit() and apply() in SharedPreferences
...I guess the @spacemanaki 's comment above is also true contains valuable information
– Aksel Fatih
Nov 8 '13 at 10:24
58
...
SQL Switch/Case in 'where' clause
...
As TomH noted in the comment to your reply below, you formed the SQL incorrectly. I tested mine in SQLServer 2005 and it worked fine.
– Bob Probst
Oct 16 '08 at 0:48
...
Singular or plural controller and helper names in Rails
...ntifiers I define as a singular in one place are then used in their plural forms in other places. For example, I might want to define something like this in config/routes.rb:
resource :dashboard, :only => [:show]
and then I want a controller DashboardController to display summary information...
Is #pragma once a safe include guard?
...lation. I recognize that is non-standard, and thus could pose a cross-platform compatibility issue.
14 Answers
...
xkcd style graphs in MATLAB
...(-x/3) + 3;
y2 = 3*exp(-(x-7).^2/2) + 1;
%# jitter
x = x+randn(size(x))*0.01;
y1 = y1+randn(size(x))*0.01;
y2 = y2+randn(size(x))*0.01;
%# plot
figure('color','w')
hold on
plot(x,y1,'b','lineWidth',3);
plot(x,y2,'w','lineWidth',7);
plot(x,y2,'r','lineWidth',3);
xlim([0.95 10])
ylim([0 5])
set(gca...
For each row in an R dataframe
...w(tab)),
function(i) unclass(tab[i,,drop=F])
)
Or a faster, less clear form:
rows = function(x) lapply(seq_len(nrow(x)), function(i) lapply(x,"[",i))
This function just splits a data.frame to a list of rows. Then you can make a normal "for" over this list:
tab = data.frame(x = 1:3, y=2:4, z=...