Documents 4. Relational Databases. Levels of Abstraction in data defined by various “schema” levels *...

4. Relational Databases Levels of Abstraction in data defined by various “schema” levels Schemas are defined using Data Definition Languages or DDLs; data are modified/queried…

Documents Section 4

4. Relational Databases Levels of Abstraction in data defined by various “schema” levels Schemas are defined using Data Definition Languages or DDLs; data are modified/queried…