Advanced Database Systems $$ Week #$1$ Assignment $1$

Review Questions

Module $16$

$16\mathrm{.}1.$ What is the difference between primary and secondary storage?

$16\mathrm{.}2.$ Why are disks, not tapes, used to store online database files?

$16\mathrm{.}3.$ Define the following terms: disk, disk pack, track, block, cylinder, sector, interblock gap, and read$/$write head.

$16\mathrm{.}4.$ Discuss the process of disk initialization.

$16\mathrm{.}5.$ Discuss the mechanism used to read data from or write data to the disk.

$16\mathrm{.}6.$ What are the components of a disk block address?

$16\mathrm{.}10.$ Discuss the techniques for allocating file blocks on disk.

$16\mathrm{.}12.$ What is the difference between static and dynamic files?

$16\mathrm{.}16.$ Discuss the techniques for allowing a hash file to expand and shrink dynamically. What are the advantages and disadvantages of each?

$16\mathrm{.}17.$ What is the difference between the directories of extendible and dynamic hashing?

$16\mathrm{.}19.$ Describe the mismatch between processor and disk technologies.

$16\mathrm{.}20.$ What are the main goals of the RAID technology? How does it achieve them?

Module $17$

$17\mathrm{.}1.$ Define the following terms: indexing field, primary key field, clustering field, secondary key field, block anchor, dense index, and nondense $($sparse$)$ index.

$17\mathrm{.}2.$ What are the differences among primary, secondary$,$ and clustering indexes? How do these differences affect the ways in which these indexes are implemented? Which of the indexes are dense, and which are not?

$17\mathrm{.}3.$ Why can we have at most one primary or clustering index on a file, but several secondary indexes?

$17\mathrm{.}4.$ How does multilevel indexing improve the efficiency of searching an index file?