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Unique fields that allow nulls in Django
...o actually protect data integrity. Data may be entered via import scripts, from the shell, through an API or any other means. Much better to override the save() method than to make custom cases for every form that might touch the data.
– shacker
Jul 27 '16 at 1...
Removing multiple keys from a dictionary safely
I know how to remove an entry, 'key' from my dictionary d , safely. You do:
14 Answers
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Catching an exception while using a Python 'with' statement
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from __future__ import with_statement
try:
with open( "a.txt" ) as f :
print f.readlines()
except EnvironmentError: # parent of IOError, OSError *and* WindowsError where available
print 'oops'
If you want d...
Get properties and values from unknown object
From the world of PHP I have decided to give C# a go. I've had a search but can't seem to find the answer of how to do the equivalent to this.
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Is quitting an application frowned upon?
... there. Using startForeground(int, Notification) I can almost stop Android from killing the Service...?
– Ted
Jan 9 '10 at 18:30
67
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What is Data Transfer Object?
...Transfer Object is an object that is used to encapsulate data, and send it from one subsystem of an application to another.
DTOs are most commonly used by the Services layer in an N-Tier application to transfer data between itself and the UI layer. The main benefit here is that it reduces the amoun...
Mechanisms for tracking DB schema changes [closed]
...version number of the database. The N.sql files are crafted by hand, to go from version (N-1) to version N of the database.
They can be used to add tables, add columns, migrate data from an old to a new column format then drop the column, insert "master" data rows such as user types, etc. Basically...
How to read a text file reversely with iterator in C#
...a large file, around 400K lines and 200 M. But sometimes I have to process from bottom up. How can I use iterator (yield return) here? Basically I don't like to load everything in memory. I know it is more efficient to use iterator in .NET.
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Remove all whitespace in a string
I want to eliminate all the whitespace from a string, on both ends, and in between words.
10 Answers
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What does it mean to inflate a view from an xml file?
...o android development and keep coming across references to Inflating views from a layout xml file. I googled and searched the development guide but still wasn't able to pick up a sense for what it means. If someone could provide a very simple example, it'd be much appreciated.
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