LIS278 EXAM 2

The Crow's foot symbol with two parallel lines indicates ____ cardinality.

(1,1)

A table that is in 1NF and includes no partial dependencies is said to be in ____.

2NF

____ is a generic entity type that is related to one or more entity subtypes.

An entity supertype

____ relationships are most common.

Binary

The ____ command would be used to delete the table row where the P_CODE is 'BRT-345'.

DELETE FROM PRODUCT WHERE P_CODE = 'BRT-345';

To list all the contents of the PRODUCT table, you would use ____.

SELECT * FROM PRODUCT;

The SQL command that modifies an attribute's data values in one or more table's rows is ____.

UPDATE

A table that has all key attributes defined, has no repeating groups, and all its attributes are dependent on the primary key, is said to be in ____.

1NF

Partial completeness is symbolized by ____.

a circle over a single line

When you issue the DELETE FROM tablename command without specifying a WHERE condition, ____.

all rows will be deleted

A(n) ____ entity is composed of the primary keys of each of the entities to be connected.

associative

Before converting a table into 3NF, it is imperative the table already be in ____.

2NF

A ____ entity has a primary key that is partially or totally derived from the parent entity in the relationship, and it is existent-dependent.

weak

When the PK of one entity does not contain the PK of a related entity, the relationship is ____.

weak

SQL character data format(s) is(are) ____.

CHAR and VARCHAR

____ yields better performance and greater data redundancy.

Denormalization

The SQL command that lets you add rows of data into a table is ____.

INSERT

Which of the following is used to select partial table contents?

SELECT <column(s)> FROM <Table name> WHERE <Conditions>;

Which query will output the table contents when the value of P_PRICE is less than or equal to 10?

SELECT P_DESCRIPT, P_INDATE, P_PRICE, V_CODE FROM PRODUCT WHERE P_PRICE <= 10;

Which query will output the table contents when the value of V_CODE is not equal to 21344?

SELECT P_DESCRIPT, P_INDATE, P_PRICE, V_CODE FROM PRODUCT WHERE V_CODE <> 21344;

Which of the following has the correct sequence of the SELECT statement?

SELECT-FROM-WHERE-GROUP BY-HAVING-ORDER BY

An example of a command you would use when changing data values to a PRODUCT table is ____.

UPDATE PRODUCT SET P_INDATE = '18-JAN-2004' WHERE P_CODE = '13-Q2/P2';

A ____ relationship exists when two entities are associated.

binary

BCNF can be violated only when the table contains more than one ____key.

candidate

An atomic attribute ____.

cannot be further subdivided

A ____ key is composed of more than one attribute.

composite

The associative entity is also known as a ____ entity.

composite

Data redundancy produces ____.

data integrity problems

From a strictly database point of view, ____ attribute values can be calculated from other attributes when they are needed to write reports or invoices.

derived

Attribute A ____ attribute B if all of the rows in the table that agree in value for attribute A also agree in value for attribute B.

determines

The primary key's main function is to uniquely identify a(n) ____ within a table.

entity instance or row

If an entity can exist apart from one or more related entities, it is said to be ____-independent.

existence

The property of ____ enables an entity subtype to inherit the attributes and relationships of the supertype.

inheritance

The existence of a(n) ____ relationship indicates that the minimum cardinality is at least 1 for the mandatory entity.

mandatory

A __________ is a real-world identifier used to uniquely identify real-world objects.

natural key

Within a specialization hierarchy, every subtype can have ____ supertype(s) to which it is directly related.

only one

The term "____" is used to label any condition in which one or more optional relationships exist.

optionality

Dependencies based upon only part of a composite primary key are called ____ dependencies.

partial

One important inheritance characteristic is that all entity subtypes inherit their ____ key attribute from their supertype.

primary

The most important characteristic of an entity is its ____ key, used to uniquely identify each entity instance.

primary

An attribute that is part of a key is known as a(n) ____ attribute.

prime

A ____ derives its name from the fact that a group of multiple entries of the same type can exist for any single key attribute occurrence (i.e., multi-valued attribute).

repeating group

A relational table must not contain a(n) ____.

repeating group

A(n) ____ is a query that is embedded (or nested) inside another query.

subquery

A(n) ____ is the attribute in the supertype entity that determines to which entity subtype each supertype occurrence is related.

subtype discriminator

A ________ is a primary key created by the database designer to simplify the identification of entity instances.

surrogate key

Normalization works through a series of stages called normal forms. For most purposes in business database design, ____ stages are as high as you need to go in the normalization process.

three

A ____ exists when a nonkey attribute is functionally dependent upon another nonkey attribute.

transitive dependency

A ____ relationship exists when an association is maintained within a single entity.

unary

Disjoint, or, non-overlapping, subtypes are subtypes that contain a(n) ____ subset of the supertype entity set. That is, each entity instance of the supertype can appear in only one of the subtypes.

unique