COMPUTER APPLICATIONS
DATABASE MANAGEMENT SYSTEMS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Subschema
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Logical view
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Physical view
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Schema
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External-level schema
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Detailed explanation-1: -A database schema defines how data is organized within a relational database; this is inclusive of logical constraints such as, table names, fields, data types, and the relationships between these entities.
Detailed explanation-2: -schema. (1) A description of the data elements in a database, the relationships among them, and the logical model used to organize and describe the data.
Detailed explanation-3: -Database Schema: The description of a database. Includes descriptions of the database structure and the constraints that should hold on the database. Schema Diagram: A diagrammatic display of (some aspects of) a database schema. Database Instance: The actual data stored in a database at a particular moment in time.
Detailed explanation-4: -A database model shows the logical structure of a database, including the relationships and constraints that determine how data can be stored and accessed. Individual database models are designed based on the rules and concepts of whichever broader data model the designers adopt.