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| |
| Welcome to Lens! |
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| Lens provides an Unified Analytics interface. Lens aims to cut the Data Analytics silos by providing a single view of data across multiple tiered data stores and optimal execution environment for the analytical query. It seamlessly integrates Hadoop with traditional data warehouses to appear like one. |
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| At a high level the project provides these features - |
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| * Simple metadata layer which provides an abstract view over tiered data stores |
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| * Single <<shared schema>> server based on the Hive Metastore - This schema is shared by data pipelines (HCatalog) and analytics applications. |
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| * <<OLAP Cube QL>> which is a high level SQL like language to query and describe data sets organized in data cubes. |
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| * A <<JDBC driver>> and <<Java client libraries>> to issue queries, and a CLI for ad hoc queries. |
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| * <<Lens application server>> - a REST server which allows users to query data, make schema changes, scheduling queries and enforcing quota limits on queries. |
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| * <<Driver based architecture>> allows plugging in reporting systems like Hive, Columnar data warehouses, Redshift etc. |
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| * <<Cost based engine selection>> - allows optimal use of resources by selecting the best execution engine for a given query based on the query cost. |
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| The following diagram shows Lens architecture. |
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| [/images/arch.png] Lens Architecture |
