Bissoy.com
Doctors Medicines MCQs Q&A

Related Questions

If access paths are available on all the conditions of a disjunctive selection, each index is scanned for pointers to tuples that satisfy the individual condition. This is satisfied by
Consider two database relations R and S having 3 tuples in R and 2 tuples in S. what is the maximum number of tuples that could appear in the natural join of R and S?
Which one of the following provides the ability to query information from the database and to insert tuples into, delete tuples from, and modify tuples in the database?
In a ____________ the system scans each file block and tests all records to see whether they satisfy the selection condition.
There are blank spaces in the following passage which have been numbered . These numbers are printed below the passage and against each some words are suggested . Find out the word that best fit the blank spaces. Global Strategies to control infective disease have historically included the erection of barriers to international travel and ___ (24) _______. Keeping people with such deadly disease outside national borders has ___ (25) _______ as an important public health policy in the human immunodeficiency virus (HIV) epidemic . Betwwn 29 and 50 countries ___ (26) _____ to have introduced border restrictions on HIV _ positive foreigners ,usually those planning an ___ (27) ___ stay in the country , such as students , workers or seamen.
X-rays, MRI scans and CT scans belong to which type of test for diagnosis of Vasculitis?
Which of the following is used at the end of the view to reject the tuples which do not satisfy the condition in where clause?
Which of the following Relational Algebra operations can be used when you want to keep all the tuples of the first relation irrespective of whether or not they have matching tuples in the second relation?
Consider two relations R1(A, B) with the tuples (1, 5), (3, 7) and R2(A, C) = (1, 7), (4, 9). Assume that R(A, B, C) is the full natural outer join of R1 and R2. Consider the following tuples of the form (A, B, C): a = (1, 5, null), b = (1, null, 7), c = (3, null, 9), d = (4, 7, null), e = (1, 5, 7), f = (3, 7, null), g = (4, null, 9). Which one of the following statements is correct?
SQL allows duplicate tuples in relations, and correspondingly defines the multiplicity of tuples in the result of joins. Which one of the following queries always gives the same answer as the nested select * from R where a in (select S.a from S)