Part I

Open a Access Database• Blank Database• Database Wizard• Existing Database

(last five databases saved on the computer appear in the list box. If the file you want does not appear select More files…)

The database window

• This window will appear after selecting the database. Note it has the 6 database objects each on its own tab.

Database Tables

• Used to store data • holds field names,

field descriptions and data for each field of each record

• underlying structure for data stored in a database

Table Selection

• Datasheet View• Design View• Table Wizard• Import Table• Link Table

Design ViewDatabase Table

Columns in the Table Design

• Field Name• Data Type - 10 types that are listed in a

drop down box by clicking the arrow button on the column

• Description

Access Data Types

• Text - any combination of alphabetic and numeric characters, such as names, addresses, and telephone numbers, that are not use in calculations (default)

• memo - long entries requiring multiple lines of text, such as detailed descriptions and performance notes

Access Data Types

• Number - numeric values, such as the number of items or number of days worked that might be used in calculations

• Date/Time - dates, such as date hired, and times, such as 1:00

• Currency - monetary values, such as salary

Access Data Types

• AutoNumber - numbers assigned by Access to uniquely identify each record; these values cannot be changed, deleted, or edited

• Yes/No - Single-character entry fields that are marked when the status of the field is true (yes) or left blank when the status is false (no)

Access Data Types• OLE object - fields that may be linked to an

object, such as a picture or a document• Hyperlink - fields linked to other objects,

Web pages, or documents that appear when the field when the field is clicked.

• Lookup Wizard - fields that enable you to access a value from a table or list of values

Filled in Table Design

Datasheet View

The Field Name(s)

There are no records for this Database (yet)

Records Added to Datasheet

Two Views

• Datasheet view - you see the field names as column headings and records as row. View multiple records on the screen.

• Form view - forms use the fields and data that are stored in database tables to see one record on-screen at a time.

Form View

Maintenance

• Change is inevitable. You will need add, delete modify information in your db

• find, update, insert, replace, delete, sort, and filter and query.

Find, Filter, Query

Query languageformat

examples

Query Language

• ask questions about the database• find the records which match a certain

criteria

Find or Filter or Query

• Which one? Depends on preciseness.• All display or filter only the record(s) that

match a specific criteria • note that there is also a FIND command in

the word processing and spreadsheet tools.

Find• usually used for error correction • used in searching for a particular value in a record.

This command works the same way as it did for the spreadsheet.

• you type in the dialog box • Find what: the entry you want to find. Depending

on whether you unselected “current field”, Find searches each field (in the table) to look for a match.

To Find Records in a DB Table• The binoculars on the toolbar• also can do find/replace (Edit->Replace)

Find

• Find can a search criterion with text or values anywhere in the table. This can be inexact. For example, if you used the find command to find an employee named Brown, the records of employees who live in the town Brown or on the street Brown could also be displayed.

Filters

• A Filter is an exact match. In a filter, Access only matches within a certain field. So in our last example, you would tell Access to find only NAMES (the field name) that are equal to Brown. Thus the other Brown matches are eliminated.

Filters• To display (filter) only the record or records

that satisfy a criterion.• Filter by selection is the simplest type of filter.• All you need to do is give Access an example

of the data you want by selecting the data within the table, and then clicking the Filter by Selection button on the Form View toolbar (the sieve with the lighting bolt)

Filter

• In order to have all the records once again displayed, you remove the filter by clicking the Remove Filter button on the form toolbar. ( the sieve by itself icon)

Filter/Query• Not saved• only within a single

table• displays all the fields

of “filtered” records• no other functions

• Can be saved (it is one of the 6 objects)

• multiple tables• displays only the fields

you specified• queries can also be used

to insert new values, modify field values and perform calculations on field values

Database WindowQueries Tab

Three options you can do in queries section

Previously Saved queries

Queries• Click on tab marked Queries on the

Database Window• There are three button on this window:

– Open - If a previously saved query is highlighted, clicking this button will display the results of this query.

– Design - If a previously saved query is highlighted, clicking this button will display the design query window filled in with the settings for this query.

– New - An empty design query window will be displayed

Queries• Note the table(s) used in the query display at

the top. • If you clicked the Design button, the table(s)

used in this saved query will be displayed.• If you clicked the New button, you will be

given the opportunity of selecting the tables through the Show Table.

Show Table

Tables saved for this database

To add tables to the query, highlight the table name and click Add. When finished click Close

Query Design Window

Back to Queries slide

The Query Design Window• A Window that isolates the important parts of a query. (Design view) • Two Important parts to the Window:

– Table(s) used in the query (top half)– The Query Grid

...

Parts of the Query Design Window

the table(s) used in the query

Customers

*

Customer Id

First Name

Last Name

Address

Table name

Example of a selected table to use in a query, appears in the top half of the Query Design Window

Field Names

Parts of the Query Design Window

the query grid

Field:Table:Sort:Show:CriteriaOr:

Drop down box of the Field Names from the selected tables

Field

• Drop down box, depends on the tables you selected to include either when the show table dialog box appeared (New) or from the original query (Design) . Once selected, the fields from the selected tables will be used in the query.

Table:

• You can select several tables for a query operation.

• Once you have selected the Field , this entry is automatically entered by Access. Access will enter the table name of the field you selected.

Sort: • You have the option of sorting the matching records• Just left click on the box and a drop down menu will

appear,• Ascending, Descending and none• Can sort on more than one field, the first field listed

(the leftmost) is the major key.• Remember only the query is sorted not the original

table(s)

Show:

• If you want this field data to appear in the results

• An empty Show box indicates that the field data will not appear in query results.

• A checked Show box indicates that the field data will appear in query results.

• Objective: remove unnecessary or duplicate fields

Criteria

• The final part, the criteria, (the comparison), determines how the query will do its comparisons.

• Using expressions (just like Excel), combinations of field names, constant values, arithmetic and logic operators, you can restrict the number of records returned by a query

Our Question (Query)?

Customers

*

Customer Id

First Name

Last Name

Address

Who are our customers with the first name of John? (list them alphabetically)

Select the Customers database

This can be answered by a completing a Query Design Window.

Filled in Query Design Window to Answer our

Question

Field:Table:Sort:Show:CriteriaOr:

Customers

*

Customer Id

First Name

Last Name

Address

Display in alphabetical order the last names of customers with the first name of John

First NameCustomers

Ascending

“John”

Last NameCustomers

The Results• A list will appear when the run command is

clicked, the ! Icon.Last Name

Black

Braithwaite

Dewey

Dickenson

Dobbins

Duran*

Only Last Name field data displays

Also note that the Johnaton(s) are not listed

Must use wild cards *

“John*”

• When you entered in the string John, Access will automatically place the quotes

• John “John”• If you entered the string John*, Access will

automatically change the field to • John* Like “John*”• Or you can put these in yourself.

Access Automatic “FILL”

String Criteria• We can “match” strings for text type fields• We can use the wild cards * and ? for substitution of characters• * - 0 or more character substitution• Like “John*”

– matches John, Johnaton, Johns, Johnstone– but not Jon, Jjohn

• ? only one match and not anymore • Like “285?5???”

– matches 285 5555, 285- 5555 – but not 765-285-5555, 1-285-5555, 285-51111

Our Next Question?

Customers

*

Customer Id

First Name

Last Name

Address

Who are our customers with the first name of John or Susan? (list them alphabetically)

Our database

This can be answered by a completing a Query Design Window.

Design Query

Field:Table:Sort:Show:CriteriaOr:

Customers

*

Customer Id

First Name

Last Name

Address

Display in alphabetical order the last names of customers with the first name of John or Susan

First NameCustomers

Ascending

“John”

Last NameCustomers

“Susan”

The Results• A list will appear when the run command is

clicked, the ! Icon.Last Name

Black

Braithwaite

Dewey

Dickenson

Dobbins

Duran

Doolittle*

Only Last Name field data displays

Also you note that the Johnaton(s) and Susanne(s) are not listed.

Must use wild cards * in strings “John*” “Susan*”

OR

• connectors• allows you to link comparisons to make it

possible for you to analyze data in various ways

• logical operators, because they act in comparisons the way mathematical operators work in the Spreadsheet

Or Conjunction

• when one or more of the conditions needs to be “true” we use the or conjunction

• color equal to green OR color equal to yellow • color equal to green OR part number equal to

948• one listed in the criteria row, the other in the

or row

Numeric Criteria - Logic Operators

• Greater than (>)• Less than (<)• equals (=)• greater than or equal to (>=)• less than or equal to (<=• not equal to (<>• (same as Excel If expressions)

Design Query

Field:Table:Sort:Show:CriteriaOr:

Customers

*

Customer Id

First Name

Last Name

Address

Total Purchase

Age

Tablename

Display in descending order the total purchase ofcustomers who are under 30 years of age

Total PurchaseCustomers Customers CustomersDescending

Last Name Age

<30

The Results• A list will appear when the run command is

clicked, the ! Icon.

Total Purchase

$1900.50

$1410.26

$1167.88

$900.88

$469.34

$367.99*

The query is sorted by the amount of the total purchase

Last Name

Smith

Buy

Jones

Smith

Feather

Johnson

Age

24

21

26

20

14

29

Design Query

Field:Table:Sort:Show:CriteriaOr:

Orders

*

Customer Id

Order #

Product ID #

Quantity

Unit Price

Date of Purchase

Date of Payment

Tablename

Display all orders which have not been paid by oldest date

Order #Orders Orders Orders

Date of Purchase Date of Payment

Is Null

Ascending

Criteria

• Null - the absence of data - an empty field. • If a field has no entry, it is called a null

value. This is not the same as a space or zero!

• The computer treats dates as if they were sequential numbers that increase with time

The Results• A list will appear when the run command is

clicked, the ! Icon.

Order #

146678

145778

145807

145900

145910

145950*

The query is sorted by the date of purchase

Note that the Date of Payment could have been marked to not display.

Date of Purchase

3/10/2000

3/12/2000

3/15/2000

3/19/2000

3/21/2000

3/24/2000

Date of Payment

Design Query

Field:Table:Sort:Show:CriteriaOr:

Orders

*

Customer Id

Order #

Product ID #

Quantity

Unit Price

Date of Purchase

Date of Payment

Tablename

Display all orders which were paid this month

Order #Orders Orders Orders

Date of Purchase Date of Payment

>=4/1/2000

Ascending

The Results• A list will appear when the run command is

clicked, the ! Icon.

Order #

146578

145578

145607

145600

145710

145750*

The query is sorted by the date of purchase

Note that the Date of Payment could have been marked to not display.

Date of Purchase

3/02/2000

3/02/2000

3/05/2000

3/05/2000

3/06/2000

3/06/2000

Date of Payment

4/2/2000

4/2/2000

4/4/2000

4/5/2000

4/6/2000

4/6/2000

• When you entered in the string >4/1/2000, Access will automatically place the # s

• >=4/1/2000 >=#4/1/2000#• Or you can put these in yourself.

Access Automatic “FILL”

Simple Selection Query

Field:Table:Sort:Show:CriteriaOr:

Customers

*

Customer Id

First Name

Last Name

Address

Display all of the customers with the nameJohn Smith

First NameCustomers

“John”

Last NameCustomers

“Smith”

And Conjunction

• The AND conjunction says that both conditions must be present for the record (row) to be queried

• to combine criteria with AND, place the criteria on the same line

Combining Multiple Conjunctions

• when combining with all Ors - no problem• when combining with all Ands - no problem• when combining with both Ands and Ors -

order is important

Design QueryCustomers

*

Customer Id

First Name

Last Name

Age

Display in alphabetical order the last names of customers with the first name of John or Susan that are older than 50 years of age.

Field:Table:Sort:Show:CriteriaOr:

First NameCustomers

“John”

Ascending

Last NameCustomers

“Susan”

AgeCustomers

>50

First Name Last Name Age

David Done 33

Fred Flinstone 55

Susan Johnson 43

Susan Peters 34

John Peters 39

John Smith 55

Susan Smith 52

The Records in the Database

First Name Last Name Age

Susan Johnson 43

Susan Peters 34

John Smith 55

Susan Smith 52

Result of Query

Note that the records matched any record with the first name of Susan and records that had the first name of John and were older than 50

(FirstName = “John” AND Age > 50) OR FirstName = “Susan”

First Name Last Name Age

John Smith 55

Susan Smith 52

But what if wanted only those records with first name of Susan who were age 50 or older or records with the first name of John who were age 50 or older … or

Note that the records matched any record with the first name of Susan and records that had the first name of John and were older than 50

(FirstName = “John” OR FirstName = “Susan”) AND age > 50

Design QueryCustomers

*

Customer Id

First Name

Last Name

Age

Display in alphabetical order the last names of customers with the first name of John or Susan that are older than 50 years of age.

Field:Table:Sort:Show:CriteriaOr:

First NameCustomers

“John”

Ascending

Last NameCustomers

“Susan”

AgeCustomers

>50

>50

First Name Last Name Age

John Smith 55

Susan Smith 52

Result:

Note that the records matched any record with the first name of Susan who was older than 50 years of age or records that had the first name of John who were older than 50 years of age.

(FirstName = “John” and age > 50) OR

( FirstName = “Susan” and age > 50)

Three fields using AND and OR

Meaning

• Be careful of the wording when designing queries.

• For example if I asked you to give me a list of classes that are held at 9:00 A.M and 10:00 A.M, I am using the word AND to mean both (not the connective AND)

• BOTH-> OR

Questions