Database Systems. DBMS MS Access

What is "required"

Indicates that some data must be entered in the field before the record can be saved.

What is a foreign key

It is the "Primary Key" of a table which exists in a joint table

What's an example of a DBMS

MySQL Microsoft Access SQL server

What are the different types of relationships

One to one A record in one table relates to one and only one record in a second table • Primary key value from one table only exists once in the second table as a foreign key One to many • A record in one table may have more than one related record in a second table • Primary key value in the first table may be used several times in the second table Many to many Many records in table 1 are related to many records in table 2

Rules of database theory

Reduce redundancy and Inconsistency • Eliminate entering data multiple times; this will reduce potential for entering same data incorrectly Facilitate Maintenance • Need to accurately change data (ideally once) Maintain Accuracy • Relationships can help reduce potential for errors Simplify Information Retrieval • Extracting information should be easy and quick

What is input mask?

Specifies how a field looks as the user enters data into it

What is the first database object to be created

Tables

What are the database components

Tables Forms Reports Queries

What is format

The way text appears on a page.

What is indexed

Use to set a single - field index.

What is field size

indicates the maximum length of a data field

What is a database?

organized collection of data that can be easily accessed, retrieved, managed and updated

What is validation text

specifies the text in the error message that appears when a user violates a validation rule

Why are primary keys important

• Allows relationships between tables • Enforces the integrity of the table • Avoid administrative confusion in entering the data

What is datasheet view?

Allows you to add/enter, edit, delete, and search for data in a spreadsheet - like environment This is where you enter/input the records to your database tables

What is design view

Allows you to modify the design of new and existing tables

What is default value

Assigns a value that Access inserts into the field in each new record you add to the table.

What is validation rule

Checks the data entered against a criteria to prevent invalid or incorrect entries.

What is a database management system (DBMS)?

Database Management System (DBMS) is a software designed to store, retrieve, define, and manage data in a database.

What is decimal places

Determines how many decimal places are displayed and printed in number and currency fields

What is allow zero length

Determines whether a zero length strings are not valid entries

Flat File vs Relational Database

Flat file contains one single table Relational has multiple tables with relationships

Referential integrity

1. You cannot add a record to a related table unless there is already a matching record in the primary table 2. You cannot delete a record from a primary table while matching records still exist in the related table

What is a primary key

A column or set of columns in a database table that serves as a unique identifier. It is a key in a relational database that is unique for each record

Why are forms useful

Easy way to guide people into entering data correctly • With forms, it's possible to enter data into multiple tables at once, all in one place

What are the different types of field properties

Field size Validation rule Validation text Input mask Caption Format Decimal places Default value Required Indexed Allow zero length

What are database forms

Forms are used for entering, modifying, and viewing records from a table or a query

What is caption

Gives a label for access to use in reports and forms

What are queries

Queries are a way of searching for and retrieving specific data from one or more tables

What is a record

Records refers to rows, or horizontal groupings of unique field data.

What are database reports

Reports offer you the ability to present your data in print

What is a field

Set of data values, of the same data type. Referred to as a column or an attribute

What are the different data types

Short text Long text Number Currency Yes/No Date/Time Autonumber

What are tables

Tables are database objects that contain or hold all the data in a database

Why are reports useful

Useful because they allow you to present components of your database in an easy - to - read format • Reports can be created from a table or a query