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How to query as GROUP BY in django?
...Another solution is to use the group_by property:
query = Members.objects.all().query
query.group_by = ['designation']
results = QuerySet(query=query, model=Members)
You can now iterate over the results variable to retrieve your results. Note that group_by is not documented and may be changed in ...
Boolean vs boolean in Java
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It should be noted the a Boolean actually has 3 states... true, false and null where a boolean has the logical 2 states (true and false)
– respectTheCode
Jun 6 '14 at 15:46
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ASP.NET_SessionId + OWIN Cookies do not send to browser
...do a little more work for each request.
Back to our login problem
With all these pieces your scenarios can be explained.
Case 1 - Session was never set
System.Web.SessionState.SessionStateModule, s_sessionEverSet property is false. No session id's are generated by session state module and Syst...
Programmatically select text in a contenteditable HTML element?
In JavaScript, it's possible to programmatically select text in an input or textarea element. You can focus an input with ipt.focus() , and then select its contents with ipt.select() . You can even select a specific range with ipt.setSelectionRange(from,to) .
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JavaScript/regex: Remove text between parentheses
...the parentheses are in the middle of a string, the regex above will remove all the whitespace around them. This is probably not good.
– Nigel Johnson
Nov 13 '17 at 11:42
1
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Java Multiple Inheritance
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@MoritzPetersen If you really want to go into reusing abstractions and giving meaningful names, probably AbstractEquidae would be more suitable than AbstractHorse. It would be strange to have a zebra extend an abstract horse. Nice answer, by the way....
How to timeout a thread
... SSCCE:
package com.stackoverflow.q2275443;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
public clas...
How to add Options Menu to Fragment in Android
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Call the super method:
Java:
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
}
@Override
public void onCreateOptio...
MongoDB: How to query for records where field is null or not set?
...ount({sent_at: {$exists: false}})
If its there and null, or not there at all:
db.emails.count({sent_at: null})
Refer here for querying and null
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How do I pass an object from one activity to another on Android? [duplicate]
...tom classes across activities. I have found this very useful.
Here is a small snippet of code I am using
CustomListing currentListing = new CustomListing();
Intent i = new Intent();
Bundle b = new Bundle();
b.putParcelable(Constants.CUSTOM_LISTING, currentListing);
i.putExtras(b);
i.setClass(this,...