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How can I get Docker Linux container information from within the container itself?
I would like to make my docker containers aware of their configuration, the same way you can get information about EC2 instances through metadata.
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How to set auto increment primary key in PostgreSQL?
I have a table in PostgreSQL with 22 columns, and I want to add an auto increment primary key.
7 Answers
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NULL vs nil in Objective-C
In observeValueForKeyPath:ofObject:change:context: - why do the docs use NULL instead of nil when not specifying a context pointer?
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'IF' in 'SELECT' statement - choose output value based on column values
...unctions.html.
Additionally, you could handle when the condition is null. In the case of a null amount:
SELECT id,
IF(type = 'P', IFNULL(amount,0), IFNULL(amount,0) * -1) as amount
FROM report
The part IFNULL(amount,0) means when amount is not null return amount else return 0.
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ObservableCollection not noticing when Item in it changes (even with INotifyPropertyChanged)
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The ContentList's Set method will not get called when you change a value inside the collection, instead you should be looking out for the CollectionChanged event firing.
public class CollectionViewModel : ViewModelBase
{
public ObservableCollection<EntityViewModel> ContentList...
Tying in to Django Admin's Model History
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The admin history is just an app like any other Django app, with the exception being special placement on the admin site.
The model is in django.contrib.admin.models.LogEntry.
When a user makes a change, add to the log like this (...
Oracle: how to UPSERT (update or insert into a table?)
The UPSERT operation either updates or inserts a row in a table, depending if the table already has a row that matches the data:
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@RequestParam vs @PathVariable
...t is the difference between @RequestParam and @PathVariable while handling special characters?
7 Answers
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How to lay out Views in RelativeLayout programmatically?
I'm trying to achieve the following programmatically (rather than declaratively via XML):
9 Answers
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Is it possible to use argsort in descending order?
Consider the following code:
9 Answers
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