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A comment on B-Trees - Balanced Search Trees for Slow Storage. Parent comment

Re: B-Trees - Balanced Search Trees for Slow Storage by ajross on Monday July 07, 2008 @11:39AM (#238710)
B-trees (and related data structures) are pervasive in the real world. Pretty much any application that requires high speed access from disk uses them. Think about filesystems, databases, etc... They're hugely useful.

But they're not useful for the same purpose as a hash table, which is also a pervasive data structure, but for a different problem area: constant time access to in-memory data.

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Re: B-Trees - Balanced Search Trees for Slow Storage by noodle on Monday July 07, 2008 @11:53AM (#238725)
yes, i know. my point is, try finding an entry-level position that requires knowledge and experience of b-trees and not hashtables.
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Re: B-Trees - Balanced Search Trees for Slow Storage by cdr on Monday July 07, 2008 @12:33PM (#238776)
Like a lot of things, it's good to know for the interview but most likely useless after that.
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Re: B-Trees - Balanced Search Trees for Slow Storage by lampy on Monday July 07, 2008 @12:39PM (#238780)
Try finding a senior-level engineering position that doesn't require knowledge of B-trees or similar computer science topics.
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Re: B-Trees - Balanced Search Trees for Slow Storage by Tamerlin on Monday July 07, 2008 @12:47PM (#238792)
So far in my experience the companies hiring want you to know that sort of thing, but that knowledge is largely wasted at most jobs.
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Re: B-Trees - Balanced Search Trees for Slow Storage by Tamerlin on Monday July 07, 2008 @12:46PM (#238790)
Knowing what a binary tree is turned out to be overkill for even most of the senior developer positions I've had.
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Re: B-Trees - Balanced Search Trees for Slow Storage by dfranke on Monday July 07, 2008 @03:45PM (#239100)
Hash tables can be used on disk as well.
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Re: B-Trees - Balanced Search Trees for Slow Storage by Tamerlin on Monday July 07, 2008 @07:41PM (#239329)
That's certainly true. They're also useful for distributed caches, but that doesn't make B-trees any less useful when the situation calls for it.
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Re: B-Trees - Balanced Search Trees for Slow Storage by dfranke on Monday July 07, 2008 @08:54PM (#239395)
B-trees are basically the only sane option if you ever need to do range queries. Hash tables tend to outperform them a bit on all other operations.
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