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Debug vs. Release performance
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The C# compiler does not do tail call optimizations; the jitter does. If you want an accurate list of what the C# compiler does when the optimize switch is on, see blogs.msdn.com/ericlippert/archive/2009/06/11/…
– Eri...
Why not use Double or Float to represent currency?
...llar, usually all you need is to be able to store multiples of 10-2, so it doesn't really matter that 1/3 can't be represented.
The problem with floats and doubles is that the vast majority of money-like numbers don't have an exact representation as an integer times a power of 2. In fact, the only ...
How to test if a string is basically an integer in quotes using Ruby
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You've got the right idea, but it doesn't match binary or hex literals (see my edited solution below).
– Sarah Mei
Aug 6 '09 at 3:56
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Fastest way to check a string contain another substring in JavaScript?
...ffice 2013 App, using Microsoft's Office Javascript API, and using indexOf doesn't work. I'm not sure why. Using Regex though does. This is an edge case, but others might run into the same issue.
– Andy Mercer
Jun 6 '14 at 18:37
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What are the pros and cons of performing calculations in sql vs. in your application
...ext switches round trip. Yes: that is expensive. A "native" DBMS operation does all the hard work to minimise disk-I/O's (system calls) but manages to fetch more than one row per system call. Row at a time takes at least four system calls.
– wildplasser
Sep 22 ...
Database Structure for Tree Data Structure
...n choosing a model are:
1) Frequency of structure change - how frequently does the actual structure of the tree change. Some models provide better structure update characteristics. It is important to separate structure changes from other data changes however. For example, you may want to model a co...
Postgresql - change the size of a varchar column to lower length
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Change varchar length does not rewrite the table. It just check the constraint length against the entire table exactly as CHECK CONSTRAINT. If you increase length there is nothing to do, just next insert or updates will accept bigger length. If y...
How to write a:hover in inline CSS?
... @Kato while that is a great link, and I really wish it worked, sadly it does not. Just to confirm, I tested using the syntax style="{color:green;} :hover { color: red; }" and firefox managed to color the link green, but ignored the hover. Chrome ignored both. Continued testing would be pretty poi...
How to check if a file is a valid image file?
... if he's really testing for "valid" images; the presence of a magic number doesn't guarantee that the file hasn't been truncated, for example.
– Ben Blank
May 20 '09 at 18:11
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What is the purpose of XORing a register with itself? [duplicate]
xor eax, eax will always set eax to zero, right? So, why does MSVC++ sometimes put it in my executable's code? Is it more efficient that mov eax, 0 ?
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