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Rails: How can I set default values in ActiveRecord?
...st this case like so:
self.number ||= 0.0 if self.has_attribute? :number
and for a boolean column...
self.bool_field = true if (self.has_attribute? :bool_value) && self.bool_field.nil?
Also note that the syntax is different prior to Rails 3.2 (see Cliff Darling's comment below)
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Space between two rows in a table?
...class spaceUnder. This will make it possible to use nested tables. (Cell C and D in the example code.) I'm not too sure about browser support for the direct child selector (think IE 6), but it shouldn't break the code in any modern browsers.
/* Apply padding to td elements that are direct child...
Assign variable in if condition statement, good practice or not? [closed]
...ng whatever the value evaluates to be after the assignment. Is this understanding right?
– Michael Mao
Apr 5 '10 at 2:10
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Git 'fatal: Unable to write new index file'
I've seen many of the other threads about this and they don't help.
24 Answers
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while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
...hat the compiler would generate the same byte code for while(True): pass and while(1): pass , but this is actually not the case in python2.7.
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Eclipse git checkout (aka, revert)
...Staging" view, right click the deleted file in the "Unstaged Changes" list and select "Replace with HEAD Revision"
– Vlasta Dolejs
Sep 5 '17 at 8:03
add a comment
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Could not load file or assembly 'xxx' or one of its dependencies. An attempt was made to load a prog
...ecked out a revision from Subversion to a new folder. Opened the solution and I get this when run:
9 Answers
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Fastest way to get the first object from a queryset in django?
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Use the convenience methods .first() and .last():
MyModel.objects.filter(blah=blah).first()
They both swallow the resulting exception and return None if the queryset returns no objects.
These were added in Django 1.6, which was released in Nov 2013.
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How do I reflect over the members of dynamic object?
I need to get a dictionary of properties and their values from an object declared with the dynamic keyword in .NET 4? It seems using reflection for this will not work.
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Restore a postgres backup file using the command line?
I'm new to postgresql, and locally, I use pgadmin3. On the remote server, however, I have no such luxury.
24 Answers
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