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Optimise PostgreSQL for fast testing
.... For example, PostgreSQL 9.2 significantly improves the speed of TRUNCATE and of course adds index-only scans. Even minor releases should always be followed; see the version policy.
Don'ts
Do NOT put a tablespace on a RAMdisk or other non-durable storage.
If you lose a tablespace the whole datab...
What is the difference between LINQ ToDictionary and ToLookup
What is the difference between LINQ ToDictionary and ToLookup? They seem to do the same thing.
2 Answers
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Where to define custom error types in Ruby and/or Rails?
...ou define exceptions in this way:
gem_dir/lib/gem_name/exceptions.rb
and defined as:
module GemName
class AuthenticationError < StandardError; end
class InvalidUsername < AuthenticationError; end
end
an example of this would be something like this in httparty
For Ruby on Rails
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MySQL error code: 1175 during UPDATE in MySQL Workbench
...update the column visited to give it the value 1. I use MySQL workbench, and I'm writing the statement in the SQL editor from inside the workbench. I'm writing the following command:
...
Case objects vs Enumerations in Scala
...es. However, I find in general that enumerations are a bit clumsy in Scala and have the feel of an awkward add-on, so I now tend to use case objects. A case object is more flexible than an enum:
sealed trait Currency { def name: String }
case object EUR extends Currency { val name = "EUR" } //etc.
...
Difference between std::result_of and decltype
I have some trouble understanding the need for std::result_of in C++0x. If I understood correctly, result_of is used to obtain the resulting type of invoking a function object with certain types of parameters. For example:
...
SecItemAdd and SecItemCopyMatching returns error code -34018 (errSecMissingEntitlement)
...rror -34018. This doesn't match any of the documented keychain error codes and can't be consistently reproduced. (happens maybe 30% of the time, and it's not clear to me why it happens). What makes debugging this problem very difficult is the total lack of documentation. Any idea what causes this an...
How to recursively find the latest modified file in a directory?
...n BSD, the options for formatting is different (-f "%m %N" it would seem)
And I missed the part of plural; if you want more then the latest file, just bump up the tail argument.
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What are the benefits of learning Vim? [closed]
As a programmer I spend a lot of hours at the keyboard and I've been doing it for the last 12 years, more or less. If there's something I've never gotten used to during all this time, it's these annoying and almost unconscious constant micro-interruptions I experience while coding, due to some of th...
How to get all possible combinations of a list’s elements?
I have a list with 15 numbers in, and I need to write some code that produces all 32,768 combinations of those numbers.
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