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International School of Stavanger

Access 2007 Handouts for Computer Studies


CONTENTS What is a database made of? ................................................................................................................................. 3 Fields ................................................................................................................................................................... 3 Records ............................................................................................................................................................... 3 Files ..................................................................................................................................................................... 3 Key Fields ............................................................................................................................................................ 4 Data types ............................................................................................................................................................... 4 Logical/Boolean .................................................................................................................................................. 4 Alphanumeric/Text ............................................................................................................................................. 5 Numbers (Real and Integer) ............................................................................................................................... 5 Integers ........................................................................................................................................................... 5 Real ................................................................................................................................................................. 5 Date & Time ........................................................................................................................................................ 6 Selecting appropriate data types ........................................................................................................................ 6 Creating a report in Access ..................................................................................................................................... 8 Modifying reports, using layout view ................................................................................................................... 10 Opening layout view ......................................................................................................................................... 10 Understanding Layout view .............................................................................................................................. 10 Adjusting column width .................................................................................................................................... 10 Reorganising columns ....................................................................................................................................... 10 Deleting information ........................................................................................................................................ 10 Logos ................................................................................................................................................................. 10 Page Setup ........................................................................................................................................................ 10 Queries ................................................................................................................................................................. 11 Creating Queries ............................................................................................................................................... 11 Understanding Query Design view ................................................................................................................... 12 Query properties .............................................................................................................................................. 13 Criteria .............................................................................................................................................................. 14 <>, <, >, Between .. And .. ............................................................................................................................. 14 Nulls .............................................................................................................................................................. 14 OR and IN(.., .., ..).......................................................................................................................................... 14 Importing csv files in Access ................................................................................................................................. 15 Wildcard Searches ............................................................................................................................................ 18 Summary in access ............................................................................................................................................... 19 Run time calculations in Access ............................................................................................................................ 21


WHAT IS A DATABASE MADE OF? FIELDS Each piece of information in a database is stored in a field; these individual data items have a data type and can only hold information of that specific type.

EXAMPLE: Name

Harriet Johnson

RECORDS Several fields grouped together are referred to as a record. Each record will hold several pieces of information relating to one specific thing (i.e. a person)

EXAMPLE: Name

Harriet Johnson

Born

11. June 1974

Address

18 Elm Street

Phone

51554300

Married

Yes

Education

MBA

Occupation

Accountant

FILES A file is a collection of records; each record is structured in the same manner. This means that each record has the same data fields, but stores information about different items (i.e. a person)

EXAMPLE: Name

Harriet Johnson

Peter Parker

Clark Kent

Born

11. June 1974

06. May 1978

01. February

Address

18 Elm Street

22 Elm Street

19 Smalville

Phone

51554300

51554301

51554302

Married

Yes

No

Yes

Education

MBA

Photography

Journalism

Occupation

Accountant

Photograph

Journalist


KEY FIELDS In order to separate the different records in a database we often use a key field. This field contains an ID or something similar that is unique to that record.

EXAMPLE: ID

11067565723

06067865542

01026556816

Name

Harriet Johnson

Peter Parker

Clark Kent

Born

11. June 1974

06. May 1978

01. February 1965

Address

18 Elm Street

22 Elm Street

19 Smalville

Phone

51554300

51554301

51554302

Married

Yes

No

Yes

Education

MBA

Photography

Journalism

Occupation

Accountant

Photograph

Journalist

DATA TYPES All fields have a data type and can only hold information of that specific type. We have four main data types: Logical/Boolean, Alphanumeric/Text, Numbers (Real and Integer) and Date

LOGICAL/BOOLEAN Boolean, or logical data, can only hold either TRUE or FALSE. However this can also be expressed as yes, no, on, off or with tick boxes

EXAMPLES TRUE FALSE YES NO ON OFF


ALPHANUMERIC/TEXT This data type can hold any character you can input, including symbols (¤, &, %, ”, @, etc.) spaces, normal text and numbers

EXAMPLES DOG “A little mouse” ABC123 enquiries@bbc.co.uk

NUMBERS (REAL AND INTEGER) Numbers are, well, numbers. However we separate between two main types of numbers; Integer and Real

INTEGERS An integer is a whole number, meaning that it cannot hold decimals. An integer can either be positive or negative.

EXAMPLES

12 45 1274 1000000 -3 -5735 Real Numbers

REAL A real number can hold both integers and numbers that have decimals. A real number can either be positive or negative

EXAMPlES

1 1.4534 946.5 -0.0003 3.142


DATE & TIME A Date & Time field can hold a specific date and/or time. It is usually preformatted so that all dates within the database appear similar.

DATE EXAMPLES 25/10/2007 12 Mar 2008 10-06-08

TIME EXAMPLES 11am 15:00 3:00pm 17:05:45

SELECTING APPROPRIATE DATA TYPES In a database all fields must have a data type and it is important that we select one that is appropriate for the information we wish to store in that specific field. Different data types have different properties, it is for instance not possible to use text for a mathematical function.

EXAMPLE: Numeric (Integer) >

ID

11067565723

Text >

Name

Harriet Johnson

Date >

Born

11. June 1974

Text >

Address

18 Elm Street

Phone

51554300

Married

Yes

Text >

Education

MBA

Text >

Occupation

Accountant

Numeric (Integer) > Boolean >


THE ACCESS INTERFACE The interface is divided into three main areas:

C - Currently open object

A - Ribbon

A - Ribbon This is common for the Office 2007 interface and gives you access to the different tools available. B - Objects in the database This lists all the different objects in the database, objects may include: -

Tables

-

Queries

-

Forms

Reports C - Currently open object In this area the current object will be opened D - Field properties When youâ&#x20AC;&#x2122;re working on a table in design view you can access the different field properties here.

B - Objects in database

D - Field properties (only available in form design view)


REATING A REPORT IN ACCESS 1.

Select the table you want to create a report from

2.

Start the report wizard under the create ribbon

3.

Select the fields you want to include in your report and add them by clicking the ‘ > ‘ button You can add all fields by clicking the ‘ >> ‘ button

4.

Click ‘Next’


5.

If you want to group the information by a field select it and click the ‘ > ‘ button

6.

Click ‘Next’

7.

Select how you want to sort the data in your report

8.

Click ‘Next’

9.

Select the layout of your report

10. Select if the report should be printed in portrait or landscape 11. Click ‘Next’ 12. Select a style for your report 13. Click ‘Next’ 14. Name your report appropriately 15. Click ‘Finish’


MODIFYING REPORTS, USING LAYOUT VIEW You can make some basic adjustments to your reports, after you have created them, using layout view.

OPENING LAYOUT VIEW You can access layout view by clicking the view button in the home ribbon, provided that you’ve opened the report object If you cannot find the home ribbon you’re probably in print preview and need to close it by clicking the ‘Close Print Preview’ button in the Print Preview ribbon

UNDERSTANDING LAYOUT VIEW In layout view you can select and modify the different elements of a report by clicking on them. Elements are things like text boxes and column headings. The dotted lines shows the margins and where the page breaks are.

ADJUSTING COLUMN WIDTH If the information in a column only shows up as ##### it is because that column is to narrow, you can adjust it by selecting the column heading and dragging the dividers between each column If you double click on the dividers between each column it will adjust the column with to the heading automatically. Sometimes it might be necessary to adjust the columns so that they all fit on one page Always make sure that all the information is showing in all the fields

REORGANISING COLUMNS If you want the columns in a different order you can select the column heading and drag it to where you want it.

DELETING INFORMATION You can delete elements in your report by selecting them and clicking the delete button. If you delete a column heading you will also delete the entire column of information.

LOGOS You can insert a picture as a logo in your report by clicking the logo button, under the format ribbon.

PAGE SETUP You can modify the page setup for a report in layout view by selecting the Page Setup ribbon Use this to change between portrait and landscape without having to recreate the report.


QUERIES In access you can create queries to search and filter data for reports

CREATING QUERIES

1.

Select the table you want to base you query on

2.

Start the Query Wizard under the Create ribbon

3.

Select the Simple Query Wizard and click ‘OK’

4.

Add the fields you want to use in your query and click ‘Next’

5.

You now get two options: a. Detail (shows every field of every record In most cases this is the option you need to use, we will modify the query to fit our needs later. b.

Summary This option will allow you to make summary queries, for instance calculate the average of a number, grouped by department

Select the type of query you need and click ‘Next’ 6.

Name your query appropriately and click ‘Finish’


UNDERSTANDING QUERY DESIGN VIEW You can adapt the basic query, created with the wizard, to your needs by opening it in Design view. Query design view is divided into two parts, Tables and Properties.

Tables

Properties

Tables shows the different tables associated with this query Properties lists the different fields in use and the properties/criteria set for each of them You can add fields to your query by dragging them from the tables and dropping them in the properties area.


QUERY PROPERTIES Under the properties tab each column contains one field and the different properties for it are listed in the separate rows. The different rows are: -

Field The name of the field

-

Table Table the field is from

-

Sort Will the query sort records based on information in this field? Information can be sorted both ascending and descending

-

Show If checked this field will show up in result table, if unchecked it will not.

-

Criteria Records are selected based on the criteria set in this field.

-

or Additional criteriaâ&#x20AC;&#x2122;s If a record meets the criteria in either the Criteria field or the or field it will be displayed, you can add more criteriaâ&#x20AC;&#x2122;s by using the unlabeled rows below or.


CRITERIA There are several criteriaâ&#x20AC;&#x2122;s that you can use to select records from a table The simplest criteria is the exact match. Just enter the value desired in the field's criteria section. Remember that by using the Show option to eliminate the field from the display, you can specify criteria in fields the user never sees.

<>, <, >, BETWEEN .. AND .. You can also retrieve records where a field does not have a particular value by using "< >" followed by the value you don't want. You can also use Not to exclude specific data. Similarly, you can use >, <, >=, or <= for ranges. To select records with values between two values, use the BETWEEN .. AND .. syntax.

NULLS To select records with Null values, enter Is Null. The opposite is Is Not Null. For text fields, remember that zero length strings ("") are not nulls.

OR AND IN(.., .., ..) To select records where a field can have one of several values, use the OR command. You can simply say: "MD" or "DC" or "VA".


IMPORTING CSV FILES IN ACCESS

1.

Open the database you want to import the data into, or create a new blank one

2.

Select the ‘External Data’ ribbon

3.

Click the Text ‘file’ button under the import group

4.

Select the data source by clicking the ‘browse’ button The data source is the .csv file

5.

Choose where to import the data Make sure you select the appropriate import option: a. Import the source data into a new table in the current database This will create a new table where the data is stored, this is the option you will use the most b.

Append a copy of the records to the table: This will add the data you’re importing to an existing table in the database

c.

Link to the data source by creating a linked table This will create a table that is just referencing the external data, We will never use this feature in class, DO NOT SELECT IT

6.

Click ‘ok’ to open the Import text wizard

7.

Select Delimited in the first screen and click next When importing a .csv file the data are separated (delimited) by character, usually commas


8.

Select the delimiter Usually this will be a comma. The data should show up in separate columns.

9.

If the first row contains the field name, check this box At this point your wizard should look something like this:

10. Click next 11. Make sure to select the correct data type for each field Do this by: a. Selecting the field (each column represents a different field) b. Checking the field options above the table


12. Check that access will handle the different data correctly Do this by: a. Clicking the ‘Advanced’ button b. Select the correct date order (DMY = Date Month Year, MDY = Month Day Year) c. Select the correct decimal symbol (usually period as comma is used to separate fields d. Click ‘OK’

Select date order Select decimal symbol

13. Choose whether you want to add a primary key or not and click ‘next’ You can let access add a new one, define a field as one or choose to create table without it. 14. Name your table and click ‘Finish’

If there are Boolean (Yes/No)fields Once imported Access will display boolean field information as 0 and -1, to change this: a. Open the table b. Go to design view c. Select the Boolean field d. Under the field properties change the format to: Yes/No


WILDCARD SEARCHES Sometimes, you need to search for a particular letter or digit. Combined with the Like command, wildcards let you specify such criteria. These are the wildcard characters Microsoft Access uses: ? Single Character * Any number of Characters # Single Digit [..] Character List [!..] not in Character List

EXAMPLE

-

If you are interested in a text field where the second letter is "a", the criteria would be: Like "?a*". If you were seeking values where the second letter could be an "a" or "e", the criteria would be: Like "?[ae]*". The opposite of this (all values that do not have "a" or "e" as the second letter) is performed by adding an "!": Like "?[!ae]*". Finally, to select a range of letters (say "a" through "e"), add a dash between the letters: Like "?[a-e]*". To search for a wildcard character, enclose the value in brackets. For instance, to find values that end in a question mark, use this: Like "*[?]"


SUMMARY IN ACCESS The summary function in access can be used to do simple calculations on numeric fields, grouped by another field in the table. To create summaries in access we use queries: 1.

Create a query, containing only the field you want to group by and the one you want to make a summary of

2.

In the Query design click the Totals button under the design ribbon

3.

This will make another row, called Total, between the Table and Sort rows visible

4.

Under the field you want to do your calculation, select an appropriate option from the dropdown: Sum – Calculates the total of the values in each group Avg – Calculates the average of the values in each group Min – Finds the lowest value in each group Max – Finds the highest value in each group Count – Shows how many records there are in each group First – Shows the first record in each group Last – Shoes the last record in each group

5.

Make sure the field you want to group by says Group By in the totals row

6.

Run the query


Example

Consider the following data table:

Name

Department

Sales

John

Shoes

39 000 NOK

Bob

Jackets

15 000 NOK

Spencer

Jackets

16 000 NOK

Laura

Shoes

21 000 NOK

Mary

Shoes

24 000 NOK

Jane

Jackets

45 000 NOK

We want to find out, what the average sale, per department is, a summary query can tell us this. By telling access that you want the average sale, the program will group people by department, add together their total sales and divide it by the number of people:

To do this we need the following query:

And it gives us the table: Department

Sales

Jackets

25 333,33 NOK

Shoes

28 000 NOK


RUN TIME CALCULATIONS IN ACCESS When creating queries we can ask access to perform some calculations each time we run the query, and show the results in a separate column. 1.

Create a query with the fields that you want to include

2.

In an empty column, enter the name of the new field, followed by the calculation

The colon ( : ) signifies the end of the field name

Name of the new field

Operator for the calculation (divide)

Name: Number / 3 A field used in the calculation

3.

A number used in the calulation

Each time you run the query it will perform the calculation for each record and display the result


EXAMPLE Consider the following data table:

Name

Department

Sales

John

Shoes

39 000 NOK

Bob

Jackets

15 000 NOK

Spencer

Jackets

16 000 NOK

Laura

Shoes

21 000 NOK

Mary

Shoes

24 000 NOK

Jane

Jackets

45 000 NOK

Each employee gets 1 bonus point for each 175 NOK they sell for and can use these to buy things in the store. We want to create a query that calculates this and displays the results in a column called Bonus. To do this we need to use the following formulae:

To do this we need the following query:

And it gives us the table: Name

Sales

Bonus

John

39 000 NOK

222,85

Bob

15 000 NOK

85,71

Spencer

16 000 NOK

91,42

Laura

21 000 NOK

120

Mary

24 000 NOK

137,14

Jane

45 000 NOK

257,14


/Access-2007