Is a search key a) a primary key, b) any candidate key, or c) any attribute or collection of attributes? In Figure 10.10, the records are stored in order of their primary key (the ID attribute), but there are also pointers from one field to the next. Why are there pointers when the records are already stored in the right order? Is it because a) when records are added or deleted it may be difficult to keep records in the right order, b) pointers allow for faster search, b) the pointers provide a cross-check in the case of an error? True or false: in a dense index, there must be pointer from the index to every record in the file. This is Fig. 11.3 of our text 10101 32343 76766 10101 Srinivasan Comp. Sci.65000 12121 Wu 15151 Mozart Music 22222 Einstein Phvsics 32343 El Said Histor 33456 Gold 45565 Katz 58583 Califieri Histo 76543 Sin 76766 Crick 83821 Brandt Comp. Sci. 92000 98345 Kim Finance 90000 40000 95000 60000 87000 Physics Comp. Sci. 75000 62000 Finance 80000 Biolo 72000 Elec. En 80000 cepts 6th Edition 11.8 GSilberschatz, Korth and Sudarshan Is the index in the figure a) a clustering index, or b) a nonclustering index? Which is generally fastest for locating a record: a) a dense index, b) a sparse index, or c) both are equally fast? Suppose we have a dense index on a table, and a row of the table is deleted. To keep the index up to date, how many rows of the index will need to be deleted? a) none, b) 0 or 1, depending on the table, or c) at least 1? What combination can't be used? a) dense, clustering indexes, b) dense, non-clustering indexes, c) sparse, clustering indexes or d) sparse, non-clustering indexes? In section 11.2.4 of the text, the authors state that an index is normally created by default for the primary key of a table, and that the index is used when a new record is inserted to ensure uniqueness of the primary key value. How would this uniqueness check be performed? a) the primary key values of table records would be compared to rows of the index, b) a linear scan would be made of the index, or c) a binary search would be made of the index