Queries and Forms

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Transcript Queries and Forms

Access Queries and Forms
Simple Queries
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To create an Access query, don’t use the
query wizard. Instead, create query in Design
view
Let’s see how Access does it
Copy the Pets database to your desktop
Then open the Pets database
Queries
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You can look for something after a certain
date IF the data was stored as date/time and
you say >1/1/2004
Dates should be entered with # before and
after the date, and can be in many different
formats, ie #1/1/2004#, #January 1, 2004#,
#1-Jan-2004#
Queries
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Logical OR - You can look for records in the
state of Indiana or Illinois by saying “IL” OR
“IN”
You can also say: In (“IL”, “IN”, “OH”)
Logical AND - you can make multiple entries
in the query boxes. For example, in the State
field enter “IL” and then in the Size field enter
<3
Queries
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Logical AND - You can also use an AND in
one field. For example, in the Size field you
can enter >=3 AND <=9
A slightly easier way of doing this is using the
BETWEEN operator: Between 3 and 9
Possible operators include =, <>, <, >, <=,
>=
Queries That Calculate
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When performing a query, you can aggregate the data
You can perform a Count, Sum, Avg, Max, Min, StDev,
Var(iance), First, and Last
Count, First, and Last can be performed on types
counter, number, currency, date/time, yes/no, text,
memo, and OLE object
The others on counter, number, currency, date/time,
and yes/no
Example
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Say you have a database for a vet that treats
dogs. Each dog treated has an entry
including ID, weight, and height
If you want to find the average weight and
height of all pets: (you may have to click on View / Totals)
Field: Pet ID
Weight
Height
Total: Count
Avg
Avg
Show:
X
X
X
Example
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What if you want to find the average height
and weight for all dogs?
Field:
Weight
Height
Type of Animal
Total:
Avg
Avg
Group By
Show:
X
Criteria:
X
X
“Dog”
Example
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What if you want to find the minimum and
maximum weight for all dogs?
Field: Weight
Weight
Type of Animal
Total:
Min
Max
Group By
Show:
X
Criteria:
X
X
“Dog”
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One way to start a form is to use the Form
Wizard
Let’s create a form for our Real Estate
database, for the Listings table
Download the Real Estate database to the
desktop and unzip the file
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Now go back into Design View to edit the
form
Resize windows
Move fields around
Many more properties / controls available
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Label controls – headings, labels, captions,
instructions
Text box controls – data is displayed or
entered here
Toggle buttons, option / radio buttons, check
boxes
Option group – contains multiple toggle
buttons
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List box – a pull down menu which is always
down
Combo box – a pull down menu which you
must pull down, and also lets you add an
option that is not on the list
When working with forms, notice Table
button (or Field List), Toolbox button, and
Wizard button in Toolbox
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Let’s try another example
Create a form using Name text 50, Married
Yes/No, Employed Yes/No, Home Owner
Yes/No, City text 50, and State text 2
Make Name a text box, Married a toggle
button, Employed a check box, Home Owner
an option button, City a combo box, and
State a list box
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Click on Field List button. If you can’t click
on this, click on Properties and set Record
Source to appropriate table
Click on Toolbox and make sure Wizard
button is pressed
Click on ab|, then click and drag on Name
field
Click on Toggle button, then click and drag
on Married field
Now put a caption or a picture in the toggle
button using Properties
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Pretty much everything in Access has a list of
properties associated with it
To display properties, you can click on View
 Properties from the menu bar
Or you can right click on an item
Let’s look at some properties
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Create form for main table
On toolbox, click on subform button (make
sure the Wizard button is pressed)
Answer the wizard’s questions
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Note – if you change the data on the form,
you are changing it in the database!
You can use the form for entering new data
You can create a form for a query and if you
enter new data on the query form, it changes
the data in the table!
Let’s stop here and try our activity