What does "derivability of relation" mean when it comes to relational databases?

Expert Solution

Derivability of Relation:

The relational database theory was defined by the E. F. Codd.

In the database world, a relation is an individual table and it stores the relation between data by using the row and column concept. The row of the relation or table represents the individual record and the column represents the properties of the table.

In a relational database, a table or relation is said to be derivable from a relation set if there exists a sequence of operations like natural join, projection, permutation from relation to the set of the relations.

The operation like projection, natural join, etc can be applied in relation to extracting the desired data from the relation.

These operations will provide the correct value at any time and it will not dependent on the time.

venereology answered 2 years ago

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