About
The division relational operator permits to find values in an attribute of R that have all values of S in the attribute of the same name
There is no SQL equivalent.
Articles Related
Symbol
<MATH> \LARGE R \div S \\ or\\ \LARGE R / S </MATH>
Formula
The division of R by S that return all values of the attributes R.t that have a row with all value in S.s can be expressed as: <MATH> \LARGE R / S \equiv \{\; \left<\vec t\right> \;|\; \forall \left<\vec s\right> \in S, \left< \vec t \vec s \right> \in R \;\} </MATH> where:
- <math>\forall</math> means for all
- <math>\vec t \vec s</math> are vector
Example
