5.2

2) A key decision in the physical design process is: A) knowing the user base. B) selecting structures. C) deciding on the monitor. D) all of the above.

b

A method for handling missing data is to: A) substitute and estimate for the missing data. B) track missing data with special reports. C) perform sensitivity testing. D) all of the above.

d

A rule of thumb for choosing indexes is to: A) be careful indexing attributes that may be null. B) index each primary key of each table. C) use an index when there is variety in attribute values. D) all of the above.

d

A detailed coding scheme recognized by system software for representing organizational data is called a(n): A) DBMS code. B) data type. C) SQL. D) DB layouts.

b

A method to allow adjacent secondary memory space to contain rows from several tables is called: A) cluttering. B) clustering. C) concatenating. D) compiling.

b

All of the following are common denormalization opportunities EXCEPT: A) two entities with a one-to-one relationship. B) a one-to-many relationship. C) a many-to-many relationship with nonkey attributes. D) reference data.

b

All of the following are valid datatypes in Oracle 11g EXCEPT: A) varchar2. B) booolean. C) blob. D) number.

b

the smallest unit of application data recognized by system software is a: A) field. B) row. C) data type. D) column.

a

A command used in Oracle to display how the query optimizer intends to access indexes, use parallel servers and join tables to prepare query results is the: A) explain plan. B) show optimization. C) explain query. D) analyze query.

a

An advantage of partitioning is: A) efficiency. B) remote optimization. C) extra space and update time. D) both A and B.

a

Database access frequencies are estimated from: A) transaction volumes. B) user logins. C) security violations. D) none of the above.

a

Horizontal partitioning makes sense: A) when different categories of a table's rows are processed separately. B) when less security is needed. C) when partitions must be organized the same. D) when all of the above are true.

a

In most cases the goal of ________ dominates the design process. A) efficient data processing B) security C) quick pointer updates D) shorter design times

a

One field or combination of fields for which more than one record may have the same combination of values is called a(n): A) secondary key. B) index. C) composite key. D) linked key.

a

Which type of file is most efficient with storage space? A) Sequential B) Hashed C) Indexed D) Clustered

a

Another form of denormalization where the same data are stored in multiple places in the database is called: A) data duplication. B) data replication. C) advanced placement. D) horizontal partitioning.

b

Designing physical files requires ________ of where and when data are used in various ways. A) maps B) descriptions C) keys D) hints

b

Distributing the rows of data into separate files is called: A) normalization. B) horizontal partitioning. C) vertical partitioning. D) file allocation.

b

In which type of file is multiple key retrieval not possible? A) Sequential B) Hashed C) Indexed D) Clustered

b

Which type of file is easiest to update? A) Sequential B) Hashed C) Indexed D) Clustered

b

A contiguous section of disk storage space is called a(n): A) track. B) sector. C) extent. D) tablespace.

c

A disadvantage of partitioning is: A) simplicity. B) remote optimization. C) extra space and update time. D) shorter technology spans.

c

A method that speeds query processing by running a query at the same time against several partitions of a table using multiprocessors is called: A) multiple partition queries. B) perpendicular query processing. C) parallel query processing. D) query optimization.

c

A(n) ________ is a routine that converts a primary key value into a relative record number. A) record index calculator B) index pointer program C) hashing algorithm D) pointing algorithm

c

A(n) ________ is a technique for physically arranging the records of a file on secondary storage devices. A) physical pointer B) retrieval program C) file organization D) update program

c

All of the following are horizontal partitioning methods in Oracle EXCEPT: A) key range partitioning. B) hash partitioning. C) multivalued partitioning. D) composite partitioning.

c

An index on columns from two or more tables that come from the same domain of values is called a: A) bitmap index. B) multivalued index. C) join index. D) transaction index.

c

An integrity control supported by a DBMS is: A) substitute estimates. B) security. C) range control. D) GUI guards.

c

In which data model would a code table appear? A) Conceptual B) Logical C) Physical D) Data layout

c

Sensitivity testing involves: A) checking to see if you teeth hurt when you brush. B) seeing how accurate data are. C) checking to see if missing data will greatly impact results. D) none of the above.

c

The storage format for each attribute from the logical data model is chosen to maximize ________ and minimize storage space. A) query design B) programmer productivity C) data integrity D) data integration

c

Within Oracle, the named set of storage elements in which physical files for database tables may be stored is called a(n): A) extent. B) table. C) tablespace. D) partition.

c

________ partitioning distributes the columns of a table into several separate physical records. A) Horizontal B) Crossways C) Vertical D) Final

c

1) A requirement to begin designing physical files and databases is: A) normalized relations. B) definitions of each attribute. C) technology descriptions. D) all of the above.

d

A factor to consider when choosing a file organization is: A) fast data retrieval. B) security. C) efficient storage. D) all of the above.

d

A file organization that uses hashing to map a key into a location in an index where there is a pointer to the actual data record matching the hash key is called a: A) hashed file organization. B) hash key. C) multi-indexed file organization. D) hash index table.

d

A(n) ________ is a field of data used to locate a related field or record. A) key B) index C) lock D) pointer

d

Which of the following is an objective of selecting a data type? A) Represent a small number of possible values B) Maximize storage space C) Limit security D) Improve data integrity

d

While Oracle has responsibility for managing data inside a tablespace, the tablespace as a whole is managed by the: A) user. B) database administrator. C) application developer. D) operating system.

d

A default value is the value that a field will always assume, regardless of what the user enters for an instance of that field.

f

A file organization is a named portion of primary memory.

f

A join index is a combination of two or more indexes.

f

A key is a data structure used to determine the location of rows in a file that satisfy some condition.

f

Adding notations to the EER diagram regarding data volumes and usage is of no value to the physical design process

f

An extent is a named portion of secondary memory allocated for the purpose of storing physical records.

f

Denormalization is the process of transforming relations with variable-length fields into those with fixed-length fields.

f

Free range partitioning is a type of horizontal partitioning in which each partition is defined by a range of values for one or more columns in the normalized table.

f

Horizontal partitioning is very different from creating a supertype/subtype relationship.

f

Horizontal partitioning refers to the process of combining several smaller relations into a larger table.

f

Indexes are most useful on small, clustered files.

f

One method to handle missing values is to substitute an exact value.

f

Parallel query processing speed is not significantly different from running queries in a non-parallel mode.

f

Reduced uptime is a disadvantage of partitioning.

f

The query processor always knows the best way to process a query.

f

The smallest unit of named application data is a record.

f

Using an index for attributes referenced in ORDER BY and GROUP BY clauses has no significant impact upon database performance.

f

A hashing algorithm is a routine that converts a primary key value into a relative record number.

t

A pointer is a field of data that can be used to locate a related field or record of data.

t

A range control limits the set of permissible values that a field may assume.

t

A tablespace is a named set of disk storage elements in which physical files for the database tables may be stored.

t

Along with table scans, other elements of a query can be processed in parallel.

t

Clustering allows for adjacent secondary memory locations to contain rows from several tables

t

Denormalization almost always leads to more storage space for raw data.

t

Fast data retrieval is one factor to consider when choosing a file organization for a particular database file.

t

Hash partitioning spreads data evenly across partitions independent of any partition key value.

t

In a sequential file, the records are stored in sequence according to primary key.

t

Indexes are most useful for columns that frequently appear in WHERE clauses of SQL commands, either to qualify the rows to select or for linking.

t

One decision in the physical design process is selecting structures.

t

One objective of selecting a data type is to minimize storage space

t

Security is one advantage of partitioning.

t

Sensitivity testing involves ignoring missing data unless knowing a value might significantly change results.

t

Vertical partitioning means distributing the columns of a table into several separate physical records.

t