Streaming Processing
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Streaming Processing
Tools for streaming computation
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Hash table - Wikipedia, the free encyclopedia

In computing, a hash table (also hash map) is a data structure used to implement an associative array, a structure that can map keys to values. A hash table uses a hash function to compute an index into an array of buckets or slots, from which the correct value can be found.

Ideally, the hash function should assign each possible key to a unique bucket, but this ideal situation is rarely achievable in practice (unless the hash keys are fixed; i.e. new entries are never added to the table after it is created). Instead, most hash table designs assume that hash collisions—different keys that are assigned by the hash function to the same bucket—will occur and must be accommodated in some way.

In a well-dimensioned hash table, the average cost (number of instructions) for each lookup is independent of the number of elements stored in the table. Many hash table designs also allow arbitrary insertions and deletions of key-value pairs, at constant average (indeed, amortized[2]) cost per operation.[3][4]

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10 MapReduce Tips

Cloudera offers enterprises a powerful new data platform built on the popular Apache Hadoop open-source software package.
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The Small Files Problem

The Small Files Problem | Streaming Processing | Scoop.it
Cloudera offers enterprises a powerful new data platform built on the popular Apache Hadoop open-source software package.
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揭秘InputFormat:掌控Map Reduce任务执行的利器

揭秘InputFormat:掌控Map Reduce任务执行的利器 | Streaming Processing | Scoop.it
在这篇文章中,作者Boris Lublinsky和Mike Segel将向大家展示如何利用自定义的InputFormat类来更紧密地控制Hadoop Map Reduce作业中的Maps执行策略。...
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Twitter Engineering: A Storm is coming: more details and plans for release

Twitter Engineering: A Storm is coming: more details and plans for release | Streaming Processing | Scoop.it
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