<P> The three - schema approach, or three - schema concept, in software engineering is an approach to building information systems and systems information management that originated in the 1970s . It proposes three different views in systems development, with conceptual modelling being considered the key to achieving data integration . </P> <P> The three - schema approach provides for three types of schemas with schema techniques based on formal language descriptions: </P>

What is 3 part schema in software architecture