X -> Y means

Given the following schema, Pet (petId: integer, petType: string, petName: string) Cat (petId: integer (FK), furColor: string) Dog (petId: integer (FK), furColor: string) Bird (petId: integer (FK), canFly: boolean)   Which relational algebra statement is going to produce a list of names for striped cats?

Compared to an INNER JOIN, an OUTER JOIN may

Why it is important for all transactions to have error handling and rollback capabilities:

The condition of static equilibrium means that:

Match keywords with definitions:  

Suppose we have a relational table EMPLOYEE(EMPNO, NAME, DNO, MGR, SAL). Duplicate values in the EMPNO attribute can be allowed under relational DB design principles.   

Select ALL that apply to indexing:

What is the correct SQL syntax for selecting  Customer records with LastName alphabetically between (and including) “Hansen” and “Pettersen” ?  

Who first proposed the relational database design?