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ActiveRecord OR query
How do you do an OR query in Rails 3 ActiveRecord. All the examples I find just have AND queries.
14 Answers
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Adding elements to object
...led with last element only. e.g I have 4 different items, but in an object all 4 elements are = last value solution I found is create element = {}; inside of for, then its work properly
– Gorodeckij Dimitrij
Apr 29 at 21:54
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Why is String immutable in Java?
...le for several reasons, here is a summary:
Security: parameters are typically represented as String in network connections, database connection urls, usernames/passwords etc. If it were mutable, these parameters could be easily changed.
Synchronization and concurrency: making String immutable aut...
Comparing two files in linux terminal
There are two files called "a.txt" and "b.txt" both have a list of words. Now I want to check which words are extra in "a.txt" and are not in "b.txt" .
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What's the difference between “Layers” and “Tiers”?
...on a single
computer or even in a single process
on a single computer. All we are doing
is discussing a way of organizing a
code into a set of layers defined by
specific function.
Physical tiers however, are only about
where the code runs. Specifically,
tiers are places where laye...
Is recursion a feature in and of itself?
...int of learning a language, recursion isn't a feature. If your professor really docked you marks for using a "feature" he hadn't taught yet, that was wrong.
Reading between the lines, one possibility is that by using recursion, you avoided ever using a feature that was supposed to be a learning ou...
Accessing constructor of an anonymous class
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How would I be able to call a method in the superclass of Test from within println, when that method is overridden?
– Mark Jeronimus
Feb 25 '14 at 14:56
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How do I use ROW_NUMBER()?
...ases, despite their name, don't have a formal ordering, so if you want to call a row "1" or "10" or "1337", you need to order them first using an ORDER BY clause, which is the one that goes in the OVER (ORDER BY X) clause.
– Wtrmute
Sep 13 '17 at 0:25
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What is the error “Every derived table must have its own alias” in MySQL?
...hout their names (or aliases) so, you must give unique names (aliases) for all of your sub-queries to make dbms query engine make it's work properly."
– Bahadir Tasdemir
Apr 25 '16 at 7:33
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Execute unit tests serially (rather than in parallel)
...nit test a WCF host management engine that I have written. The engine basically creates ServiceHost instances on the fly based on configuration. This allows us to dynamically reconfigure which services are available without having to bring all of them down and restart them whenever a new service is ...