Installation Guide for i2b2 on OMOP

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The legacy i2b2 data model is comprised of a central fact table (observation_fact) surrounded by multiple dimension tables arranged in a star schema.  In the Observational Medical Outcomes Partnership Common Data Model (OMOP CDM), rather than a central fact table, we have a collection of them distinguished by domain:  procedures, condition, drug, measurement, observation, etc.  In this project, we modify the CRC to run queries against multiple domain fact tables as dictated by the metadata. 

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