Explain deductive database with example.

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 Deductive Database 

A deductive database is a database system that can make deductions (i.e. conclude additional facts) based on rules and facts stored in the (deductive) database. Datalog is the language typically used to specify facts, rules, and queries in deductive databases. A deductive database can be defined as an advanced database augmented with an inference system.

Database + Inference = Deductive database



Deductive databases

  • A deductive database system is a database system that can make deductions (ie: conclude additional facts) based on rules and facts stored in the (deductive) database.
  • Datalog is the language typically used to specify facts, rules, and queries in deductive databases.
  • Deductive databases have grown out of the desire to combine logic programming with relational databases to construct systems that support a powerful formalism and are still fast and able to deal with very large datasets.
  • Deductive databases are more expressive than relational databases but less expressive than logic programming systems
  • A database system that includes capabilities to define (deductive) rules, which can deduce or infer additional information from the facts that are stored in the database is called a deductive database.
  • Rules are specified through declarative language –we specify what to achieve rather than how to achieve it.
  • The model used for deductive databases is related to logic programming and the prolog language.



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