Relational Algebra

IWT.bz

WhyLearnRelationalAlgebra?

In order to find trends and understand the world we live in, people can compare different sets of data.

By finding relationships between differing data, we can find invisible trends in the universe.

People Restaraunt

Pizza

Venn Diagram

Relational Algebra Is the Formal languageThat runs behind SQL.

Selection

σ Selects Column

Projection

π

Selects Rows

Cross Product

XCombine

TwoRelations

Set Difference

−

Elements in One Category but aren't in another category.

Set Difference Example

Set Difference Example

Union Operator

∪Element in Both

Sets.

Union Operator Example

Intersect Operator

∩

Rename Operator

ρa / b(R)