Question

Suppose the theta join R3 :=R1⋈CR2, where C is a condition that refers to attributes of R1 and R2. Which of the followings is correct?

Select one:
a. Each tuple t1 of R1 connect with some those tuple t2 of R2 that satisfy C
b. Each tuple t1 of R1 connect with one tuple t2 of R2
c. None of the others
d. Each tuple t1 of R1 connect with all those tuple t2 of R2 that satifsy C

Answer 1

In a theta join R3 := R1⋈CR2, each tuple in R1 is connected to all tuples in R2 that satisfy the join condition.

Step-by-step explanation:

The correct answer to the question "Suppose the theta join R3 :=R1⋈CR2, where C is a condition that refers to attributes of R1 and R2" is:

d. Each tuple t1 of R1 connect with all those tuple t2 of R2 that satisfy C

This type of join in relational databases connects each tuple from one relation (R1) to all tuples in another relation (R2) that meet a specified condition (C). It is not restricted to connecting a tuple from R1 to just one tuple in R2; rather, it connects to all tuples from R2 that correspond to the join condition.