Physical Database Design A rule of thumb for choosing indexes for a relational database includes which of the following? Do not specify a unique index for the primary key of each table. Indexes are more useful for columns that do not appear frequently in the WHERE clause in queries. Be careful indexing attributes that have null values. Indexes are more useful on smaller tables. Do not specify a unique index for the primary key of each table. Indexes are more useful for columns that do not appear frequently in the WHERE clause in queries. Be careful indexing attributes that have null values. Indexes are more useful on smaller tables. ANSWER DOWNLOAD EXAMIANS APP
Physical Database Design When storage space is scarce and physical records cannot span pages, creating multiple physical records from one logical relation will minimize wasted storage space. False True False True ANSWER DOWNLOAD EXAMIANS APP
Physical Database Design Selecting a data type involves which of the following? Represent most values Improve data integrity Maximize storage space All of these Represent most values Improve data integrity Maximize storage space All of these ANSWER DOWNLOAD EXAMIANS APP
Physical Database Design Which of the following is not a factor to consider when switching from small to large block size? The length of all of the fields in a table row Random row access speed The number of columns Block contention The length of all of the fields in a table row Random row access speed The number of columns Block contention ANSWER DOWNLOAD EXAMIANS APP
Physical Database Design A bitmap index is an index on columns from two or more tables that come from the same domain of values. False True False True ANSWER DOWNLOAD EXAMIANS APP
Physical Database Design The blocking factor is: the number of physical records per page. attributes grouped together by the same primary key. attributes grouped together by the same secondary key. a group of fields stored in adjacent memory. the number of physical records per page. attributes grouped together by the same primary key. attributes grouped together by the same secondary key. a group of fields stored in adjacent memory. ANSWER DOWNLOAD EXAMIANS APP