In a                            operations do not wait for requests to produce tuples, but instead generate the tuples eagerly.

Related MCQs

• 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?
• Suppose now that R(A,B:) and S(A,B:) are two relations with r and s tuples, respectively (again, not necessarily distinct). If m is the number of (not necessarily distinct) tuples in the result of the SQL query: R intersect S; Then which of the following is the most restrictive, correct condition on the value of m?
• When transaction Ti requests a data item currently held by Tj, Ti is allowed to wait only if it has a timestamp smaller than that of Tj (that is, Ti is older than Tj). Otherwise, Ti is rolled back (dies). This is
• When transaction Ti requests a data item currently held by Tj, Ti is allowed to wait only if it has a timestamp larger than that of Tj (that is, Ti is younger than Tj ). Otherwise, Tj is rolled back (Tj is wounded by Ti). This is
• A                  on an attribute of a relation is a data structure that allows the database system to find those tuples in the relation that have a specified value for that attribute efficiently, without scanning through all the tuples of the relation.
• In a                    the system makes repeated requests for tuples from the operation at the top of the pipeline.
• The iterator maintains the                      of its execution in between calls so that successive next() requests receive successive result tuples.
• Which of the join operations do not preserve non matched tuples?
• Which of the join operations do not preserve non matched tuples?
• The                        operation, denoted by −, allows us to find tuples that are in one relation but are not in another.