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DR. E. F. Codd rules Rule 1:- All data should be stored and presented in table form. Rule 2:- All data should be accessible without ambiguity. This can be accomplished through a combination of the table name, primary key, and column name. Rule 3:- Mostly database implementation support the concept of not null field constraints that prevents null values in a specific table column.     Rule 4:- A relational database must provide access to its structure through the same tools that are used to access the data. Rule 5:- The database must support at least one language that includes functionality for data definition, data manipulation, data integrity, transaction control.    Rule 6:- Data can be presented in the different logical forms called views. Each view should support the same full range of data manipulation that you can directly access to a table. But modification is not allowed here. Rule 7:- Data can be retrieved from a relational database in sets ...