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What's the difference between `1L` and `1`?
... (or 2L , 3L , etc) appear in R code. Whats the difference between 1L and 1 ? 1==1L evaluates to TRUE . Why is 1L used in R code?
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Confusion: @NotNull vs. @Column(nullable = false) with JPA and Hibernate
...tation of JSR 303, however, it intelligently picks up on these constraints and translates them into database constraints for you, so you get two for the price of one. @Column(nullable = false) is the JPA way of declaring a column to be not-null. I.e. the former is intended for validation and the lat...
In which order should floats be added to get the most precise result?
This was a question I was asked at my recent interview and I want to know (I don't actually remember the theory of the numerical analysis, so please help me :)
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How do I focus on one spec in jasmine.js?
... can run just the whole spec by this url http://localhost:8888?spec=MySpec and a the first test with http://localhost:8888?spec=MySpec+function+1
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How to iterate a loop with index and element in Swift
Is there a function that I can use to iterate over an array and have both index and element, like Python's enumerate ?
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What exactly do “IB” and “UB” mean?
I've seen the terms "IB" and "UB" used several times, particularly in the context of C++. I've tried googling them, but apparently those two-letter combinations see a lot of use. :P
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What is the difference between sites-enabled and sites-available directory?
What is use of these two directories in apache2 and how can we do it?
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Ruby on Rails - Import Data from a CSV file
...ase table. I do not want to save the CSV file, just take the data from it and put it into the existing table. I am using Ruby 1.9.2 and Rails 3.
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Possible to do a MySQL foreign key to one of two possible tables?
...table.
Polymorphic Associations are supported by frameworks such as Rails and Hibernate. But they explicitly say that you must disable SQL constraints to use this feature. Instead, the application or framework must do equivalent work to ensure that the reference is satisfied. That is, the value ...
Why are floating point numbers inaccurate?
...t numbers are represented a lot like scientific notation: with an exponent and a mantissa (also called the significand). A very simple number, say 9.2, is actually this fraction:
5179139571476070 * 2 -49
Where the exponent is -49 and the mantissa is 5179139571476070. The reason it is impossibl...