Databases: are permanent (persistent), Related, Organized and Usually stored for a organisation
External view - what user sees, designed to be helpful for task
Conceptual view - how data is organised
Physical view - how data is actually stored
Flat file - single table, suitable for simple data requirements
Hierarchical - for when data relate to each other like branches on a tree
Serial file - one after the other, stored adjacently
Sequential - data stored in order of important keys values
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