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How do you delete an ActiveRecord object?
...
It's destroy and destroy_all methods, like
user.destroy
User.find(15).destroy
User.destroy(15)
User.where(age: 20).destroy_all
User.destroy_all(age: 20)
Alternatively you can use delete and delete_all which won't enforce :before_destroy and :after...
Does Python have a string 'contains' substring method?
...methods to make in available to your custom type.
– BallpointBen
Aug 17 '18 at 7:02
31
Just make ...
How to update PATH variable permanently from Windows command line?
... do this can be found on MSDN. The key extract is this:
To programmatically add or modify system environment variables, add them to the HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment registry key, then broadcast a WM_SETTINGCHANGE message with lParam set to the s...
Query to list all stored procedures
What query can return the names of all the stored procedures in a SQL Server database
23 Answers
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Set breakpoint in C or C++ code programmatically for gdb on Linux
How can I set a breakpoint in C or C++ code programatically that will work for gdb on Linux?
6 Answers
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Why is parenthesis in print voluntary in Python 2.7?
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In Python 2.x print is actually a special statement and not a function*.
This is also why it can't be used like: lambda x: print x
Note that (expr) does not create a Tuple (it results in expr), but , does. This likely results in the confusion between...
Can you test google analytics on a localhost address?
...ersal Analytics - analytics.js
Google released a new version of analytics called "Universal Analytics" (late 2012 or early 2013). As I write, this the program is still in BETA so the above code is still recommended for most users with existing installations of Google Analytics.
However, for new deve...
Replacing some characters in a string with another character
I have a string like AxxBCyyyDEFzzLMN and I want to replace all the occurrences of x , y , and z with _ .
5 Answers
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Check if OneToOneField is None in Django
... Thank you for this solution. Unfortunately, this doesn't work all the time. In case you want to work with select_related() now or in the future -- or maybe even to be sure you also handle other sorts of magic which may happen elsewhere -- you have to extend the test as follows: if hasat...
What are the differences between numpy arrays and matrices? Which one should I use?
...ted/numpy.matrix.html
As other answers already state that you can achieve all the operations with NumPy arrays.
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