Exam 14: Database Design

A secondary key is an alternate identifier for a database. Its value may identify either a single record or a subset of all records.

A program embedded within a table and invoked automatically by updates is called a(n):

A significant disadvantage of conventional files is their inflexibility and non-scalability.

A primary key might be created by combining two or more fields. In this situation, it is called a concatenated key.

A fixed-length record structure means that each record instance can have different fields, a different number of fields, as long as the length (size) of the record is always fixed at the same size.

The data definition language (DDL) is used to create, read, update, and delete records in the database and to navigate between different records and types of records.

___________________________ files and tables contain master and transaction file records that have been deleted from on-line storage. Thus, records are rarely deleted; they are merely moved from on-line storage to off-line storage. Their requirements are dictated by government regulation and the need for subsequent audit or analysis.

A primary key might be created by combining two or more fields. In this situation it is called a _______________ key.

In implementing a database schema, an index should be created for any nonkey attributes that were identified as subsetting criteria requirements.

SQL provides a SELECT command to select specific records from a table based on specific criteria.

A(n) _________________________ key is a field whose values identify one and only one record in a file.

Files and tables that contain master and transaction file records that have been deleted from on-line storage are known as:

A database is a collection of interrelated files.

_______________________________________ establishes which business locations need access to which logical data entities and attributes.

No two records in an employee table can have the same value for EmployeeID. This is an example of:

Database design should proceed only if the underlying logical data model is in at least 2NF.

A foreign key is a field whose values identify one and only one record in the same file.

During the creation of database schemas, NULL means the field does not have to have a value; whereas, NOT NULL means the field must have a value.

Horizontal distribution of the data means that each table or entire rows in a table would be assigned to different database servers and locations.

Transaction files or tables contain records that describe business events. The data describing these events normally has a limited useful lifetime.