edited by
293 views
0 votes
0 votes

What does the following Tuple Relational Calculus query produce?

The expression σθ1 (E1 ⋈θ2 E2) is the same as:

  1.  E1 ⋈θ1^ θ2 E2
  2.  (σθ1 E1) ∧ (σθ2 E2 )
  3.  E1 ⋈ θ1∨ θ2 E2
  4.  None of the above
edited by

1 Answer

0 votes
0 votes
What is the meaning of this line :

σθ1(E1 ⋈θ2E2)
Answer:

Related questions

1 votes
1 votes
1 answer
1
Bikram asked Nov 26, 2016
319 views
Consider the join of relation R with a relation S. If R has $m$ tuples and S has $n$ tuples, then the maximum and minimum sizes of the join, respectively, are __________....
0 votes
0 votes
1 answer
2
Bikram asked Nov 26, 2016
228 views
A functional dependency of the form x → y is trivial ify ⊆ xy ⊂ xx ⊆ yx ⊂ y