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Want to find records with no associated records in Rails
...nds).where("friends.person_id IS NOT NULL")
You can do this with Arel by setting up scopes on Friend
class Friend
belongs_to :person
scope :to_somebody, ->{ where arel_table[:person_id].not_eq(nil) }
scope :to_nobody, ->{ where arel_table[:person_id].eq(nil) }
end
And then, Pers...
Get JSF managed bean by name in any Servlet related class
...hese will return null. You'd then need to manually create the bean and use setAttribute("beanName", bean).
If you're able to use CDI @Named instead of the since JSF 2.3 deprecated @ManagedBean, then it's even more easy, particularly because you don't anymore need to manually create the beans:
@Inje...
Do you have to put Task.Run in a method to make it async?
...t>();
Task.Run(() =>
{
int result = 1 + 2;
//set the result to TaskCompletionSource
tcs.SetResult(result);
});
//return the Task
return tcs.Task;
}
private async void DoWork()
{
int result = await DoWorkAsync();
}
...
Replace a string in shell script using a variable
...
paxdiablo: set is also not necessary (and how were you going to use it anyway?). Just replace=987654321.
– Roman Cheplyaka
Jul 22 '10 at 20:26
...
Do sessions really violate RESTfulness?
...raints of REST make sense of your application. You are free to apply a subset of those constraints and you will get a subset of the benefits. However, at that point you have created your own architectural style. That's not a bad thing though, in fact that's what the first four chapters of Roy's d...
Entity Framework and Connection Pooling
...tion" error when using EF with Oracle, and couldn't figure out why. I had set the dbContext up as a class variable, instantiating it at creation. Changing it to creating the context as needed fixed all the ills of my world. Thank you!
– Fletchius
Feb 10 '17 ...
The program can't start because libgcc_s_dw2-1.dll is missing
... this is a MinGW/gcc compiler issue, rather than a Microsoft Visual Studio setup.
The libgcc_s_dw2-1.dll should be in the compiler's bin directory. You can add this directory to your PATH environment variable for runtime linking, or you can avoid the problem by adding "-static-libgcc -static-libst...
How to COUNT rows within EntityFramework without loading contents?
...
OK, yes, in that case, you'll only select a subset - that should be fine. As for the blob data - I was under the impression you could set a "deferred loading" on any column in any of your EF tables to avoid loading it, so that might help.
– marc_s
...
How to use ssh agent forwarding with “vagrant ssh”?
...e key pair I have on my host machine, using agent forwarding . I've tried setting config.ssh.forward_agent to TRUE in the Vagrantfile, then rebooted the VM, and tried using:
...
Difference between a Postback and a Callback
...f postback, but it is just a quick round-trip to the server to get a small set of data (normally), and thus the page is not refreshed, unlike with the postback...think of it as 'calling the server, and receiving some data back'.
With Asp.Net, the ViewState is not refreshed when a callback is invoke...