[Q.61] Which relational algebra operator produces a Cartesian Product of two relations R and S?
R x S denotes the Cartesian Product combining every tuple of R with every tuple of S.
[Q.62] In an Entity-Relationship (ER) Diagram, a Weak Entity Set is represented by:
Weak Entity sets (which lack a primary key) are drawn using double rectangles.
[Q.63] What type of lock allows multiple transactions to read a database item simultaneously but prevents any transaction from modifying it?
Shared (S) locks permit concurrent read access while locking out exclusive write modifications.
[Q.64] In B+ Tree indexing, data records (or record pointers) are stored exclusively in:
B+ Trees store all actual record keys/pointers in leaf nodes, keeping internal nodes purely for search routing.
[Q.65] Boyce-Codd Normal Form (BCNF) is a stricter version of which Normal Form?
BCNF addresses anomalies not covered by 3NF; every BCNF table is in 3NF.