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Rails: How do I create a default value for attributes in Rails activerecord's model? [duplicate]
...consider using the before_validation callback.
– tokland
Jul 15 '10 at 10:13
44
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HTTP headers in Websockets client API
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Updated 2x
Short answer: No, only the path and protocol field can be specified.
Longer answer:
There is no method in the JavaScript WebSockets API for specifying additional headers for the client/browser to send. The HTTP path ("GET /xyz") and protocol header ("Sec-...
How to run a Python script in the background even after I logout SSH?
I have Python script bgservice.py and I want it to run all the time, because it is part of the web service I build. How can I make it run continuously even after I logout SSH?
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Convert javascript array to string
I'm trying to iterate over a "value" list and convert it into a string. Here is the code:
14 Answers
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Django - How to rename a model field using South?
...y derives the name of the database table from the name of your model class and the app that contains it. A model's database table name is constructed by joining the model's "app label" -- the name you used in manage.py startapp -- to the model's class name, with an underscore between them.
In the ...
How to remove an element from a list by index
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Use del and specify the index of the element you want to delete:
>>> a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> del a[-1]
>>> a
[0, 1, 2, 3, 4, 5, 6, 7, 8]
Also supports slices:
>>> del a[2:4]
>...
Is there a “null coalescing” operator in JavaScript?
...t now supports the nullish coalescing operator (??). It returns its right-hand-side operand when its left-hand-side operand is null or undefined, and otherwise returns its left-hand-side operand.
Please check compatibility before using it.
The JavaScript equivalent of the C# null coalescing ope...
How can I get the SQL of a PreparedStatement?
...ou have a statement, containing placeholders
it is sent to the DB server
and prepared there
which means the SQL statement is "analysed", parsed, some data-structure representing it is prepared in memory
And, then, you have bound variables
which are sent to the server
and the prepared statement ...
Opacity of background-color, but not the text [duplicate]
.../css-background-transparency-without-affecting-child-elements-through-rgba-and-filters/
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C++ sorting and keeping track of indexes
Using C++, and hopefully the standard library, I want to sort a sequence of samples in ascending order, but I also want to remember the original indexes of the new samples.
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