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		| Paper: | 
		DAS: A Data Management System for Instrument Tests  and Operations | 
	 
	
		| Volume: | 
		485, Astronomical Data Analysis Software and Systems XXIII | 
	 
	
		| Page: | 
		61 | 
	 
	
		| Authors: | 
		Frailis, M.; Sartor, S.; Zacchei, A.; Lodi, M.; Cirami, R.; Pasian, F.; Trifoglio, M.; Bulgarelli, A.; Gianotti, F.; Franceschi, E.; Nicastro, L.; Conforti, V.; Zoli, A.; Smart, R.; Morbidelli, R.; Dadina, M. | 
	 
	
	
		| Abstract: | 
		The Data Access System (DAS) is a   and data management
   software system, providing a reusable solution for the storage of
   data acquired both from telescopes and auxiliary data sources during
   the instrument development phases and operations. It is part of the
   Customizable Instrument WorkStation system (CIWS-FW), a framework
   for the storage, processing and quick-look at the data acquired from
   scientific instruments. The DAS provides a data access layer mainly
   targeted to software applications: quick-look displays,
   pre-processing pipelines and scientific workflows. It is logically
   organized in three main components: an intuitive and compact Data
   Definition Language (DAS DDL) in XML format, aimed for user-defined
   data types; an Application Programming Interface (DAS API),
   automatically adding classes and methods supporting the DDL data
   types, and providing an object-oriented query language; a data
   management component, which maps the metadata of the DDL data types
   in a relational Data Base Management System (DBMS), and stores the
   data in a shared (network) file system. With the DAS DDL, developers
   define the data model for a particular project, specifying for each
   data type the metadata attributes, the data format and layout (if
   applicable), and named references to related or aggregated data
   types. Together with the DDL user-defined data types, the DAS API
   acts as the only interface to store, query and retrieve the metadata
   and data in the DAS system, providing both an abstract interface and
   a data model specific one in C,
   C++ and  Python. The mapping of
   metadata in the back-end database is automatic and supports several
   relational DBMSs, including MySQL, Oracle and PostgreSQL. | 
	 
	
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