AI engineering glossary · SQL databases
What is relational algebra?
Relational algebra: The formal set of operations on tables that underlies SQL: selection (filter rows), projection (pick columns), union, difference, product and join. Query optimisers rewrite queries using its equivalences. It gives SQL its mathematical foundation.
Relational algebra: an example
Selection by city = 'Pune' followed by projection onto name corresponds to SELECT name ... WHERE city = 'Pune'.
Related terms
More SQL databases terms
Where you learn it
Relational algebra is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.