Advanced queries in HBase

Posted by Teflon Ted on Stack Overflow See other posts from Stack Overflow or by Teflon Ted
Published on 2009-09-16T23:50:40Z Indexed on 2010/05/22 11:20 UTC
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Filed under:

sql

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query

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nosql

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hadoop

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hbase

Given the following HBase schema scenario (from the official FAQ)...

How would you design an Hbase table for many-to-many association between two entities, for example Student and Course?

I would define two tables:

Student: student id student data (name, address, ...) courses (use course ids as column qualifiers here)

Course: course id course data (name, syllabus, ...) students (use student ids as column qualifiers here)

This schema gives you fast access to the queries, show all classes for a student (student table, courses family), or all students for a class (courses table, students family).

How would you satisfy the request: "Give me all the students that share at least two courses in common"? Can you build a "query" in HBase that will return that set, or do you have to retrieve all the pertinent data and crunch it yourself in code?

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