Database

Database

Database Design Using Normalization has 40 Questions
Needing to using more complicated SQL in database applications is a(n) ________ of normalization.

advantage
disadvantage
either an advantage or disadvantage
neither an advantage nor disadvantage
When building a database from an existing set of tables, we may safely assume that referential integrity constraints have been enforced on the data we are given.

True
False
Eliminating modification anomalies is a(n) ________ of normalization.

advantage
disadvantage
either an advantage or disadvantage
neither an advantage nor disadvantage
Most of the time, modification anomalies cause problems that are severe enough that a table should be normalized into BCNF.

True
False
Multivalued dependencies should ________ be eliminated.

always
commonly
seldom
never
When building a database from an existing set of tables, we still need to consider normalization principles.

True
False
When assessing the table structure of an acquired set of tables with data, accessing the validity of possible referential integrity constraints on foreign keys is (part of) the:

first step.
second step.
third step.
fourth step.
We have normalized a table into BCNF if all candidate keys are determinants.

True
False
Using the SQL GROUP BY phrase with a SELECT statement can help detect which of the following problems?

The multivalue, multicolumn problem
The inconsistent values problem
The missing values problem
The general-purpose remarks column problem
We use the SQL construct COLUMNS(*) to determine the number and type of columns in a table.

True
False
When assessing the table structure of an acquired set of tables with data, determining foreign keys is (part of) the:

first step.
second step.
third step.
fourth step.
One common design problem when designing a database from existing data is the use of a single cell in one column to store multiple values of an attribute.

True
False
Creating a read-only database is a task that is ________ assigned to beginning database professionals.

always
commonly
seldom
never
In all cases, normalization into BCNF is desirable.

True
False
Each answer below shows example data from a table. Which answer is an example of the general-purpose remarks column problem?

Three columns have the values 534-2435, 534-7867, and 546-2356 in the same row.
Three rows have the values Brown Small Chair, Small Chair Brown, and Small Brown Chair in the same column.
Three rows have the values Brown, NULL, and Blue in the same column.
One row has the value "He is interested in a Silver Porsche from the years 1978-1988" in a column.
Denormalized tables are in BCNF.

True
False
For a number of reasons, normalizations is not often an advantage for a(n) ________ database.

read-only
updateable
either a read-only or an updateable
None of the above is correct.
We can eliminate modification anomalies with proper normalization that results in tables in BCNF.

True
False
Most of the time, modification anomalies are serious enough that tables should be normalized into:

1NF.
2NF.
3NF.
BCNF.
Proper normalization eliminates duplicated data.

True
False
Each answer below shows example data from a table. Which answer is an example of the missing values problem?

Three columns have the values 534-2435, 534-7867, and 546-2356 in the same row.
Three rows have the values Brown Small Chair, Small Chair Brown, and Small Brown Chair in the same column.
Three rows have the values Brown, NULL, and Blue in the same column.
One row has the value "He is interested in a Silver Porsche from the years 1978-1988" in a column.
The design guidelines and priorities for read-only databases are different because read-only databases are never updated.

True
False
When assessing the table structure of an acquired set of tables with data, determining functional dependencies is (part of) the:

first step.
second step.
third step.
fourth step.
The phrase "SALE.CNumber must exist in CUSTOMER.CNumber" is a referential integrity constraint.

True
False
Each answer below shows example data from a table. Which answer is an example of the multivalue, multicolumn problem?

Three columns have the values 534-2435, 534-7867, and 546-2356 in the same row.
Three rows have the values Brown Small Chair, Small Chair Brown, and Small Brown Chair in the same column.
Three rows have the values Brown, NULL, and Blue in the same column.
One row has the value "He is interested in a Silver Porsche from the years 1978-1988" in a column.
We use the SQL construct COUNT(*) to count the number of rows in a table.

True
False
When assessing the table structure of an acquired set of tables with data, counting the number of table rows is (part of) the:

first step.
second step.
third step.
fourth step.
When you are given a set of tables and asked to create a database to store their data, the first step is to create the new database.

True
False
If a table has been normalized so that all determinants are candidate keys, then that table is in:

1NF.
2NF.
3NF.
BCNF.
Multivalued dependencies create harmless anomalies that should be noted, but do not always need to be eliminated.

True
False
Read-only databases are ________ updated.

always
commonly
seldom
never
One common design problem when designing a database from existing data is the use of a general-purpose remarks column in the received data.

True
False
Needing to assess the validity of assumed referential integrity constraints on foreign keys is a(n) ________ of normalization.

advantage
disadvantage
either an advantage or disadvantage
neither an advantage nor disadvantage
One common design problem when designing a database from existing data is the presence of missing values, called blank values, in received data.

True
False
When assessing the table structure of an acquired set of tables with data, determining primary keys is (part of) the:

first step.
second step.
third step.
fourth step.
Normalization requires programmers to write more complex SQL.

True
False
Normalization ________ data duplication.

eliminates
reduces
increases
maximizes
One common design problem when designing a database from existing data is the presence of inconsistent values in the received data.

True
False
Each answer below shows example data from a table. Which answer is an example of the inconsistent values problem?

Three columns have the values 534-2435, 534-7867, and 546-2356 in the same row.
Three rows have the values Brown Small Chair, Small Chair Brown, and Small Brown Chair in the same column.
Three rows have the values Brown, NULL, and Blue in the same column.
One row has the value "He is interested in a Silver Porsche from the years 1978-1988" in a column.
When building a database from an existing set of tables, we may safely assume that there are no multivalued dependencies in the data we are given.

True
False