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Multiple Indexes vs Multi-Column Indexes
...ctices, Part 1
Indexes in SQL Server 2005/2008 – Part 2 – Internals
One thing to note, clustered indexes should have a unique key (an identity column I would recommend) as the first column.
Basically it helps your data insert at the end of the index and not cause lots of disk IO and Page spl...
Which is more preferable to use: lambda functions or nested functions ('def')?
... a def, just to be more readable. If the function is more complex than the ones at operator module, a def is probably better.
So, real world good lambda use cases are very rare.
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“Comparison method violates its general contract!”
Can someone explain me in simple terms, why does this code throw an exception, "Comparison method violates its general contract!", and how do I fix it?
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What Java ORM do you prefer, and why? [closed]
...oo many to be managed efficiently and there are behaviors that could drive one crazy. On the other hand i have support for major databases and never have to worry about their differences.
– marcolopes
Mar 5 '11 at 13:03
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Pimpl idiom vs Pure virtual class interface
..." instances of the class at all. When it does make sense, a polymorphic "Clone" method is usually more appropriate. Examples: A Socket class, a Database class, a "policy" class, anything that would be a "closure" in a functional language.
Both pImpl and pure abstract base class are techniques to ...
Why does ReSharper want to use 'var' for everything?
...mendations on SO). To try it out I opened up a recent ASP.NET MVC project. One of the first and most frequent things I've noticed it suggesting is to change most/all my explicit declarations to var instead. For example:
...
What is the purpose of the reader monad?
...ur program, but from the time it gets compiled! So what do you do? Well, one option would be to use the Reader monad:
computePrice :: Reader CurrencyDict Dollars
computePrice
= do currencyDict <- ask
--insert computation here
Perhaps the most classic use-case is in implementing i...
MySQL ON vs USING?
...t a couple differences are noteworthy:
ON is the more general of the two. One can join tables ON a column, a set of columns and even a condition. For example:
SELECT * FROM world.City JOIN world.Country ON (City.CountryCode = Country.Code) WHERE ...
USING is useful when both tables share a colum...
What's the best/easiest GUI Library for Ruby? [closed]
...
where do you find it now whytheluckstiff is gone?
– knoopx
Dec 16 '09 at 15:31
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When to use Storyboard and when to use XIBs
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Storyboards make working in a team harder: Because you usually only have one huge storyboard file for your project, having multiple developers regularly making changes to that one file can be a headache: Changes need to be merged and conflicts resolved. When a conflict occurs, it is hard to tell h...