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A Catalogue is RDMP's representation of one of your datasets e.g. 'Hospital Admissions'.
Having a Catalogue allows for continuity of cohort building and extraction projects long term regardless of underlying database activities e.g. moving datasets to a new server, schema changes, deprecating datasets etc.
A Catalogue consists of:
Human readable names/descriptions of what is in the dataset it is
A collection of items mapped to underlying columns in your database.
Validation rules for each of the extractable items in the dataset
Graph definitions for viewing the contents of the dataset (and testing filters / cohorts built)
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