Test Center: Slacker databases break all the old rules | InfoWorld | Test Center | March 24, 2009 | By Peter Wayner
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non-relation db comparision

Keeping your database simple and fast is often difficult if you use higher level frameworks such as ActiveRecords in Ruby or Java object persistence technologies such as Hibernate. There is a lot of magic that is happening out of sight that you have no control over. If you then have to scale your application it is often the relational database that these technologies require that becomes the performance and scaling bottleneck. Often requiring complex custom implementations of partitioning and sharding to make it work. The AWS services Amazon S3 and Amazon SimpleDB were designed to handle the dominant storage usage patterns within Amazon and they greatly reduced our need to rely on relational storage for scaling our systems. But it is almost never the case that a single storage technique is used in applications and services that need to operate at enterprise scale. For example it is a common pattern that objects stored in S3 using a primary key, have a collection of secondary keys (e.g

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