Joins Flashcards
1
Q
What does a LEFT join do?
A
Returns all records from the left table, and the matched records from the right table
2
Q
What does an Equi JOIN do?
A
The JOIN condition is equivalent to the FOREIGN KEY condition and can be derived from this.
3
Q
What does a Theta JOIN do?
A
allows for arbitrary comparison relationships, such as , >=, etc.
4
Q
What is an alias used for?
A
used as a shorthand notation for the table name
5
Q
Why must tables be properly linked?
A
Referential Integrity
