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Rails where condition using NOT NIL
...id: nil })
When working with scopes between tables, I prefer to leverage merge so that I can use existing scopes more easily.
Foo.includes(:bar).merge(Bar.where.not(id: nil))
Also, since includes does not always choose a join strategy, you should use references here as well, otherwise you may e...
Setting href attribute at runtime
...s the best way to set the href attribute of the <a> tag at run time using jQuery?
5 Answers
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How do I convert a Ruby class name to a underscore-delimited symbol?
How can I programmatically turn a class name, FooBar , into a symbol, :foo_bar ? e.g. something like this, but that handles camel case properly?
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Ruby Regexp group matching, assign variables on 1 line
I'm currently trying to rexp a string into multiple variables. Example string:
5 Answers
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Store query result in a variable using in PL/pgSQL
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I think you're looking for SELECT INTO:
select test_table.name into name from test_table where id = x;
That will pull the name from test_table where id is your function's argument and leave it in the name variable. Don't leave out the table name prefix on test_table.name or you'll g...
Gradle, “sourceCompatibility” vs “targetCompatibility”?
What is the relationship/difference between sourceCompatibility and targetCompatibility ? What happens when they are set to different values?
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Filtering a list based on a list of booleans
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You're looking for itertools.compress:
>>> from itertools import compress
>>> list_a = [1, 2, 4, 6]
>>> fil = [True, False, True, False]
>>> list(compress(list_a, fil))
[1, 4]
Timing comparisons(py3.x):
>>> ...
What is an SDL renderer?
I'm starting with SDL2 and having some trouble trying to understand what an SDL_Renderer is.
2 Answers
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How do I do a 'git status' so it doesn't display untracked files without using .gitignore?
...doesn't display untracked files without using .gitignore ? I want to get modifim>cat m>ion status information on tracked files only.
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Select distinct values from a table field
I'm struggling getting my head around the Django's ORM. What I want to do is get a list of distinct values within a field on my table .... the equivalent of one of the following:
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