WEEK 10

Database Design

TABLE INSTANCE CHARTS

Create Tables

• For the tables for the sample in the Wk10_TableInstanceChart.xlsx

TYPES OF DATA

Common Data Types in Access

• Autonumber• Text• Memo• Number• Currency• Date/Time• Yes/No

Autonumber

• Use for unique sequential numbering• Commonly used for PK (Primary Key)• Increments by 1• Automatically inserted when a record is added.

Text

• Used for text or combinations of text and numbers, such as addresses, or for numbers that do not require calculations, such as phone numbers, part numbers, or postal codes.

• Stores up to 255 characters.

Memo

• Use for lengthy text and numbers, such as notes or descriptions.

• Should be used “sparingly”, because it takes up too much room in database

• Stores up to 65,536 characters (if not more)

Number

• Use for data to be included in mathematical calculations, except calculations involving money (use “Currency” type). • When you are creating a RELATIONSHIP with an

“AUTOnumber” field with the “PARENT” table

Yes/No

• Use for data that can be only 1 of 2 possible values, such as • Yes/No, • True/False, • On/Off.

• Null values are NOT allowed

Rule

• One chart completed for each table

• Wk10_TableInstanceChart.xlsx

Review Relationship Essentials• Need a primary key• EVERY TABLE NEEDS A PRIMARY KEY• Should be 1st field

• Need a foreign key• a Foreign Key is a column in a table used to reference a

Primary Key in another table.• A table does NOT necessarily have to have a Foreign Key• Whenever you see: “MANY”—this will be the Foreign

Key

• Primary key and foreign keys are essential when you create relationships that join together multiple tables in a database

Build Time

• For each of the following scenarios:• Create and write out a business narrative • Create list of ENTITIES/tables• Create the attributes for the table• Create the ERD and the relationship rules• Create a table instance chart

HUMAN RESOURCES 2

HUMAN RESOURCES 3

CREATE TABLES IN MS ACCESS

Table Design View• Exercise:• Create table for gender

Datasheet View

• Exercise:• Add data to the gender table

Table Design View

• Exercise:• Create Ribbon > Table Design in the Tables

grouping• Identify your own PK• Moving the order of the rows

Create Table with Lookups

• Exercise:• Add data to the city entity using a look up

wizard as the data type for the province

Add Data to an Entity

• Based on another entity• Exercise:• Create the students table (studentID, fname,

lname and gender fields only)

Edit an Entity

• Exercise:• Complete the Students table• Go back and look at your default value (note it

was not added to previous records entered)

Edit Data in Datasheet View

• Exercise: • Go back and add the age group and city for

each of the students previously entered

• Datasheet view• Record count• Add a new record• Search for a record• Sort the records

COMPACTING & REPAIRING A DATABASE

• DATABASE TOOLS > COMPACT & REPAIR button• •As you add, edit, & delete objects, a

database changes in size• •To minimize the size of a database & improve

performance should be done on a regular basis• •Rearranges how a fragmented database is

stored on disk

Want More Information

• Visit the following site. http://www.functionx.com/access/index.htm

QUERIES

• Is a QUESTION to the database-asking for a “set of records” from 1 or more Tables/QueriesMS Access responds by displaying the requested datais a stored question, rather than a stored responseresults automatically update,IF table is edited, it allows you to view & operate on “selected subsets” of your data

QUERIES: DEFINITION

Northwind Database

Single Table Queries

• Select fields to display• Sort by?• Simple Conditions• When you enter text into the criteria cell your

text should be enclosed in quotes ("") to distinguish it from other expressions and operators that you may need to add.

WORKING WITH TEXT

Matching Text

OR Statement

IN Statement

NOT Statement

NOT IN Statement

LIKE “Text*” Statement

LIKE “*Text” Statement

Hybrid / Homework

• Read Calculating in Access Queries• Read Calculating Totals in Access• Read Working out Someone’s Age• Watch Multi-Table Queries Part 1 & 2

• Database Assignment Part 2

HYBRID: MYITLAB

HYBRID: MYITLAB• MYITLAB HOMEWORK:

Quiz Time