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Top candidates are Postgres, MariaDB, MySQL, SQL Server

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, Oracle.

Top candidate for Reference data is Postgres.

Minimum ANSI Requirements

SQL operations cheatsheet, James Madison: http://www.qa76.net/sql_analytics

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ANSI SQL-2016 (Most): https://en.wikipedia.org/wiki/SQL:2016 ; SQL with JSON, prone to security and governance risk. 

We will Develop a ruleset that defines what commands can be used. A list of key databases must be supported. 

Modeling Considerations

HDS will be a multi layer cube (KS a multi layer cube?  Isn't it just relational?) optimized for error free loading. The model will also provide business level views to assist with Business Requirements.

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1. Physical Tables.
   1. Staging Tables
   2. Raw Tables
   3. Transaction JSON object. 
   4. Rarely change
   5. Mix of concrete and abstract constructs to allow the schema to support new attributes easily
   6. Is under the control of the database owner.
   7. A reference implementation is provided.
   8. Must support the standing view layer.
2. Standing View Layer
   1. Views to bring raw to logical
   2. Views to allow for BU analysis with less joins
   3. More will be added with time, less governance on adding. 
   4. Represents the standard data model agreed by the community.
   5. A reference implementation is provided.
   6. If the physical tables don't match the reference model, then the database owner must implement these views.
   7. A verification test bed is provided to ensure the view layer meets expectations.
   8. Materialized as needed for performance
   9. Persistent from time of creation onwards until removed.  
3. Dynamic View Layer
   1. Support Extraction Patterns that occur multiple times
   2. May represent standing extractions, like stat reportingPersistent
   3. after deployed. Build and Tear Down in course of Extraction Transaction 
   4. Part of the standard model.
4. Query Layer
   1. An SQL processor with

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