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Rails find_or_create_by more than one attribute?
There is a handy dynamic attribute in active-record called find_or_create_by:
5 Answers
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What does |= (ior) do in Python?
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|= performs an in-place+ operation between pairs of objects. In particular, between:
sets: a union operation
dicts: an update operation
counters: a union (of multisets) operation
numbers: a bitwise OR, binary operation
In most ca...
Or versus OrElse
What's the difference between or and OrElse ?
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Python: most idiomatic way to convert None to empty string?
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I'm keeping the else, but thanks for the str(s) tip so multiple types can be handled. nice!
– Mark Harrison
Jul 1 '09 at 9:39
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How to test multiple variables against a value?
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You misunderstand how boolean expressions work; they don't work like an English sentence and guess that you are talking about the same comparison for all names here. You are looking for:
if x == 1 or y == 1 or z == 1:
x and y are otherwise evaluated on their own (F...
Correct way to use get_or_create?
I'm trying to use get_or_create for some fields in my forms, but I'm getting a 500 error when I try to do so.
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How to get the first element of the List or Set? [duplicate]
I'd like to know if I can get the first element of a list or set. Which method to use?
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What is the difference between the | and || or operators?
I have always used || (two pipes) in OR expressions, both in C# and PHP. Occasionally I see a single pipe used: | . What is the difference between those two usages? Are there any caveats when using one over the other or are they interchangeable?
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Evaluate empty or null JSTL c tags
How can I validate if a String is null or empty using the c tags of JSTL ?
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IF… OR IF… in a windows batch file
Is there a way to write an IF OR IF conditional statement in a windows batch-file?
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