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Storing money in a decimal column - what precision and scale?
I'm using a decimal column to store money values on a database, and today I was wondering what precision and scale to use.
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Grouping functions (tapply, by, aggregate) and the *apply family
...ed by the extremely popular plyr package, the base functions remain useful and worth knowing.
This answer is intended to act as a sort of signpost for new useRs to help direct them to the correct *apply function for their particular problem. Note, this is not intended to simply regurgitate or repla...
Maven in Eclipse: step by step installation [closed]
I have spent been on the Maven site reading the 5- and 30-minute tutorials, and trialing Maven out for the first time.
13 A...
C++11 introduced a standardized memory model. What does it mean? And how is it going to affect C++ p
C++11 introduced a standardized memory model, but what exactly does that mean? And how is it going to affect C++ programming?
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General suggestions for debugging in R
...r silver bullet. There are good strategies for debugging in any language, and they apply here too (e.g. read this nice article). For instance, the first thing is to reproduce the problem...if you can't do that, then you need to get more information (e.g. with logging). Once you can reproduce it, ...
How do ACID and database transactions work?
What is the relationship between ACID and database transaction?
8 Answers
8
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Objective-C formatting string for boolean?
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Shouldn't the output strings be: "Yes" and "No" :P
– Ben S
Apr 8 '10 at 22:22
131
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Should I return EXIT_SUCCESS or 0 from main()?
...IT_SUCCESS when it succeeds, just for the sake of symmetry.
On the other hand, if the program never signals failure, you can use either 0 or EXIT_SUCCESS. Both are guaranteed by the standard to signal successful completion. (It's barely possible that EXIT_SUCCESS could have a value other than 0, ...
How to define hash tables in Bash?
...e equivalent of Python dictionaries but in Bash (should work across OS X and Linux).
15 Answers
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Match everything except for specified strings
...en or blue anywhere in it. For that, anchor the regular expression with ^ and include .* in the negative lookahead:
^(?!.*(red|green|blue))
Also, suppose that you want lines containing the word "engine" but without any of those colors:
^(?!.*(red|green|blue)).*engine
You might think you can f...