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find() with nil when there are no records
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Yes, just do:
Challenge.find_by_id(10)
For Rails 4 and 5:
Challenge.find_by(id: 10)
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How can I check if a var is a string in JavaScript?
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Guys, I really would give an accepted answer to both of you, but I can't, all I can do is +1 to both, than give the accepted answer at who is more near to my specific problem, that I've not fully explained.
– vitt...
Why is Scala's immutable Set not covariant in its type?
...ameter of type A due to the contravariance of functions. Set could potentially be contravariant in A, but this too causes issues when you want to do things like this:
def elements: Iterable[A]
In short, the best solution is to keep things invariant, even for the immutable data structure. You'll...
Creating and playing a sound in swift
...member to run it this way do { (player object) } catch _ { } or your will get a bug! :)
– ParisNakitaKejser
Jun 26 '15 at 20:02
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Need to list all triggers in SQL Server database with table name and table's schema
I need to list all triggers in SQL Server database with table name and table's schema.
19 Answers
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Getting parts of a URL (Regex)
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I modified this regex to identify all parts of the URL (improved version) - code in Python ^((?P<scheme>[^:/?#]+):(?=//))?(//)?(((?P<login>[^:]+)(?::(?P<password>[^@]+)?)?@)?(?P<host>[^@/?#:]*)(?::(?P<port>\d+)?)?)?(?P<path&g...
Python argparse: default value or specified value
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import argparse
parser = argparse.ArgumentParser()
parser.add_argument('--example', nargs='?', const=1, type=int)
args = parser.parse_args()
print(args)
% test.py
Namespace(example=None)
% test.py --example
Namespace(example=1)
% test.py --example 2
Namespace(example=2)
nargs...
How to restore to a different database in sql server?
...mpCopy with the contents of your.bak.
Example (restores a backup of a db called 'creditline' to 'MyTempCopy';
RESTORE FILELISTONLY FROM DISK='e:\mssql\backup\creditline.bak'
>LogicalName
>--------------
>CreditLine
>CreditLine_log
RESTORE DATABASE MyTempCopy FROM DISK='e:\mssql\backu...
rreplace - How to replace the last occurrence of an expression in a string?
...than Alex's solution and four times faster than Mark's solution. Thanks to all for your answers!
– Barthelemy
Mar 31 '10 at 20:44
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Why do we need message brokers like RabbitMQ over a database like PostgreSQL?
...ustering options are also available.
In regards to AMQP, I would say a really cool feature is the "exchange", and the ability for it to route to other exchanges. This gives you more flexibility and enables you to create a wide array of elaborate routing typologies which can come in very handy when...