Ais Study Guide - Chapter 4

Front 1

Data Dictionary

Back 1

Info regarding the structure of the database. For each element there is a record in the data dictionary describing that element. Inputs include new or deleted data elements or changes in names, descriptions, or uses of existing elements. Outputs Include reports useful to programmers in which new systems are designed and implemented, systems are documented, and audit trails are created.

Front 2

Data Definition Language

Back 2

Build the data dictionary. Initialize or create the database. Describe the logical Views. Specify Limitation or constraints on security.

Front 3

Data Manipulation Language

Back 3

Updating portions of the database. Inserting portions of the database. Deleting portions of the database.

Front 4

Data Query Language

Back 4

Retrieving records, Sorting records, Ordering records, or Presenting subsets.

Front 5

Primary Key

Back 5

Primary key is the database attribute, or combination of attributes, that uniquely identifies a specific row in a table. The primary key cannot be null. Every column in a row must be single valued. All non-key attributes in a table should describe a characteristic of the object identified by the primary key.

Front 6

Foreign Key

Back 6

Foreign Key is a attribute in a table that is a primary key in another table. Foreign keys are used to link attributes. A foreign key must either be null or correspond to the value of a primary key in another table. Every column in a row must be single valued. All non-key attributes in a table should describe a characteristic of the object identified by the primary key.

Front 7

Normalization

Back 7

Way to design a well-structured relational database. Starts with the assumption that everything is initially stored in one large table & follows set of rules to decompose the table. Objective is to produce a set of tables in third-normal form.

Front 8

Semantic data modeling

Back 8

Way to design a well-structured relational database. Database designer uses knowledge of business processes and information needs to draw a graphical picture of what should be included in the database. The resulting graphic is used to create a set of relational tables that are in third-normal form.

Front 9

Update Anomoly

Back 9

Problem that arises when attributes that aren't characteristics of the primary key are stored in that table, then the data item is stored in many different rows.

Front 10

Insert Anomaly

Back 10

Problem that arises when attributes that aren't characteristics of the primary key of a relation are stored in the table.

Front 11

Delete Anomaly

Back 11

Problem that arises when attributes that aren't characteristics of the primary key are stored in a table, so that deleting a row from the table may result in the loss of all information about those attributes that are not characteristics of the primary key.

Front 12

Logical view of data

Back 12

How the user or programmer conceptually organizes and understands that data.

Front 13

Physical view of data

Back 13

How and where the data are physically arranged and stored.

Front 14

Files versus Databases

Back 14

A set of related records, such as all customer records, forms a file. A set of interrelated, centrally coordinated files forms a database.

Front 15

Database management system

Back 15

The interface between the database and the various application programs. The database, the DBMS, and the application programs that access the database through the DBMS are referred to as the database system.

Front 16

Database Administrator

Back 16

Responsible for the database.