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How do I get the object if it exists, or None if it does not exist?
...t in' way to do this. Django will raise the DoesNotExist exception every time.
The idiomatic way to handle this in python is to wrap it in a try catch:
try:
go = SomeModel.objects.get(foo='bar')
except SomeModel.DoesNotExist:
go = None
What I did do, is to subclass models.Manager, create ...
How do I kill background processes / jobs when my shell script exits?
I am looking for a way to clean up the mess when my top-level script exits.
13 Answers
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How do you get the “object reference” of an object in java when toString() and hashCode() have been
...in Java for debugging purposes.
I.e. to make sure that the object is the same (or different) depending on the situation.
6 ...
Accessing members of items in a JSONArray with Java
...sn't iteration with the loop make the id get assigned to int id multiple times?
– Nav
Jun 28 '16 at 10:04
For more com...
Difference between jQTouch and jQuery mobile
What is the difference between jQTouch & jQuery Mobile Framework ?
4 Answers
4
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Is it fine to have foreign key as primary key?
...entifies each record in the table, or add a new field (either an auto-incrementing integer or a GUID) to act as the primary key.
The only exception to this are tables with a one-to-one relationship, where the foreign key and primary key of the linked table are one and the same.
...
Rails hidden field undefined method 'merge' error
I wanna do something like this in rails
6 Answers
6
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Converting JSONarray to ArrayList
...ble to delete from that listview later, and since JSONArray has no .remove method (Thanks Obama), I am trying to convert it to an arraylist.
...
Internal Error 500 Apache, but nothing in the logs?
...ll be permissions denied or even an interpreter that can't be found.
This means the fault almost always lies with your script. e.g you uploaded a perl script but didnt give it execute permissions? or perhaps it was corrupted in a linux environment if you write the script in windows and then upload ...
Advantages of Binary Search Trees over Hash Tables
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Remember that Binary Search Trees (reference-based) are memory-efficient. They do not reserve more memory than they need to.
For instance, if a hash function has a range R(h) = 0...100, then you need to allocate an array of 10...