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Oracle “(+)” Operator
..."adding NULL values if no match found". For example, "a.id=b.id(+)" means allow b.id to be NULL if there is no match with a.id.
– beach
Oct 26 '10 at 5:00
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Django “xxxxxx Object” display customization in admin action sidebar
... I'd declared unicode methods for every model EXCEPT this one. :doh: Sorry all.
– patrickn
Feb 17 '12 at 23:04
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In a django model custom save() method, how should you identify a new object?
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Not all models have an id attribute, i.e. a model extending another through a models.OneToOneField(OtherModel, primary_key=True). I think you need to use self.pk
– AJP
Apr 9 '13 at 10:21
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Remove characters except digits from string using Python?
How can I remove all characters except numbers from string?
15 Answers
15
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How to replace a hash key with another key
...n't like "smart" ruby code because it takes some time to tell what it is really doing. Your solution is in other hand simple and descriptive.
– Lucas
Nov 13 '14 at 18:55
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What's the _ underscore representative of in Swift References?
...ng, s2: String) -> String {
return s1 + s2;
}
}
When you call foo(), it is called like bar.foo("Hello", s2: "World").
But, you can override this behavior by using _ in front of s2 where it's declared.
func foo(s1: String, _ s2: String) -> String{
return s1 + s2;
}
Then, w...
When is “i += x” different from “i = i + x” in Python?
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This depends entirely on the object i.
+= calls the __iadd__ method (if it exists -- falling back on __add__ if it doesn't exist) whereas + calls the __add__ method1 or the __radd__ method in a few cases2.
From an API perspective, __iadd__ is supposed to be used fo...
Is there a typical state machine implementation pattern?
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Really nice touch how NUM_STATES is defined.
– Albin Stigo
Dec 19 '15 at 19:38
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How to exit from Python without traceback?
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If sys.exit() is called in "main program stuff", the code above throws away the value passed to sys.exit. Notice that sys.exit raises SystemExit and the variable "e" will contain the exit code.
– bstpierre
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How to find out which package version is loaded in R?
... figuring out how to use my university cluster. It has 2 versions of R installed. System wide R 2.11 (Debian 6.0) and R 2.14.2 in non-standard location.
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