MySQL 2nd Edition Chapter 10

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data structure

A _______ _______ is used to refer to a model of the database rather than the database itself.

enhanced entity-relationship

A/An ______________model is a representation of the entities, or objects, of the database including the tables, views, and stored programs.

index

An _______ provides a way for a database management system to locate information more quickly. When it uses an _______, the database management system can go directly to a specific row rather than having to search through all the rows until it finds it.

connecting table

As you can see, this type of relationship can be implemented by creating a linking table, also called a _______ ________ or an associate table. This table contains the primary key columns from the two tables. Then, each table has a one-to-many relationship with the linking table.

associate table

As you can see, this type of relationship can be implemented by creating a linking table, also called a connecting table or an _______ _______. This table contains the primary key columns from the two tables. Then, each table has a one-to-many relationship with the linking table.

entity

As you design a data structure, each table represents one object, or _______, in the real-world system.

Boyce-Codd normal form

Boyce-Codd normal form

joins

Data structures that are normalized to the fourth normal form and beyond typically require more _____________________ than tables normalized to the third normal form and can therefore be less efficient.

EER diagram

EER diagram

primary key

Each table in a database should have a _____________________________ that uniquely identifies each row.

D

Figure 10-1 (Refer to figure 10-1.) Which column or columns in each table are foreign keys? -------------------------------------------------------- A) Orders: OrderID; OrderLineItems: OrderID and OrderSequence; Products: ProductID B) Orders: none; OrderLineItems: OrderID and OrderSequence; Products: none C) Orders: OrderID; OrderLineItems: OrderSequence; Products: ProductID D) Orders: none; OrderLineItems: OrderID and ProductID; Products: none

A

Figure 10-1 (Refer to figure 10-1.) Which column or columns in each table should be defined as the primary key? -------------------------------------------------------- A) Orders: OrderID; OrderLineItems: OrderID and OrderSequence; Products: ProductID B) Orders: OrderID; OrderLineItems: OrderID, OrderSequence, and ProductID; Products: ProductID and ProductName C) Orders: OrderID and OrderDate; OrderLineItems: OrderID and OrderSequence; Products: ProductID D) Orders: OrderID; OrderLineItems: OrderID; Products: ProductID

derived data

If a column doesn't depend only on the primary key, it implies that the column is assigned to the wrong table or that it can be computed from other columns in the table. A column that can be computed from other columns contains _______ _______.

orphaned row

If referential integrity isn't enforced and a row is deleted from the primary key table that has related rows in the foreign key table, the rows in the foreign key table are said to be _______, or _______ ___s.

linking table

If two tables have a many-to-many relationship, you'll need to define a _______ _______ to relate them. Then, each of the tables in the many-to-many relationship will have a one-to-many relationship with the _______ _______. The _______ _______ doesn't usually have a primary key.

declarative referential integrity

In MySQL, you can enforce referential integrity by using _______ _______ _______. To use _______ _______ _______(DRI), you define foreign key constraints.

normalized data structure

In a _______ _______ _______, each table contains information about a single entity, and each piece of information is stored in exactly one place.

unnormalized data structure

In an _______ _______ _______, a table can contain information about two or more entities. It can also contain repeating columns, columns that contain repeating values, and data that's repeated in two or more rows.

data redundancy

Normalization is a formal process you can use to separate the data in a data structure into related tables. Normalization reduces _______ _______, which can cause storage and maintenance problems.

attribute

Then, within each table, each column stores one item of information, or _______, for the entity, and each row stores one occurrence, or instance, of the entity.

instance

Then, within each table, each column stores one item of information, or attribute, for the entity, and each row stores one occurrence, or _______, of the entity.

C

To be in the Second normal form, -------------------------------------------------------- A) Every non-key column must depend on the foreign key B) Every non-key column must not depend on the entire primary key C) Every non-key column must depend on the entire primary key

C

To be in the third normal form, -------------------------------------------------------- A) every non-key column must not depend on the primary key B) every non-key column must contain repeating values C) every non-key column must depend only on the primary key. D) All of the above

entity-relationship model

To model a database and the relationships between its tables after a real-world system, you can use a technique called _______-_______ (ER) _______ing.

normal form

To normalize a data structure, you apply the _______ _______s in sequence. Although there are a total of seven _______ _______s, a data structure is typically considered normalized if the first three _______ _______s are applied.

normal forms

To normalize a data structure, you apply the ______________________ in sequence.

foreign key

To use declarative referential integrity (DFI), you define ________________________ constraints.

third

Typically, most database designers consider a database structure normalized if it's in the ________________________ normal form.

foreign key constraint

When you define _______ _______ _______s, you can specify how referential integrity is enforced when a row is deleted from the primary key table. The options are to return an error, to delete the related rows in the foreign key table, or to set the foreign key values in the related rows to null.

B

When you identify the data elements in a new database, you typically subdivide data elements -------------------------------------------------------- A) not at all B) as much as possible C) as few times as possible D) None of the above

B

Which of the following is not a good guideline for deciding when to create an index for a column? -------------------------------------------------------- A) The column contains a large number of distinct values. B) The column is frequently updated. C) The column is a updated infrequently. D) The column is frequently used in search conditions or joins.

table scan

Without an index, a database management system has to perform a _______ _______, which involves searching through the entire table.

composite index

You can create _______ _______es that include two or more columns. You should use this type of index when the columns in the index are updated infrequently or when the index covers almost every search condition on the table.

computer-aided software engineering

You can use a similar notation or develop one of your own. You can also use a CASE (_______-_______ _______ _______) tool if one is available to you.

Referential integrity

_______ _______ means that the relationships between tables are maintained correctly. That means that a table with a foreign key doesn't have rows with foreign key values that don't have matching primary key values in the related table.

Normalization

_______ is a formal process you can use to separate the data in a data structure into related tables. _______ reduces data redundancy, which can cause storage and maintenance problems.

denormalization

denormalization

domain-key normal form

domain-key normal form

enhanced entity-relationship model

enhanced entity-relationship model

entity-relationship modeling

entity-relationship modeling

multivalued dependency

multivalued dependency

transitive dependency

transitive dependency


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