MS ACCESS Tables
Summary
- Introduction
to Tables and How to Build a New Database
- Creating
Tables in Datasheet View and Design View
- Working
with Data on Sorting and Filtering
1. Introduction

Creating a New Database
First, open MS Access 2007. To build
a new database, choose New Blank
Database. By selecting New
Blank Database, a panel will show up on the right, which allows us to
create a blank database by entering the database name and choosing the location
where on the computer we want to create the new database. We can also create a
new database from other database template. For this session, we will focus on creating
a database from a blank one, so click New Blank Database à Blank Database.

Fig. 1: Creating a New Database
Once you created a blank database
and type the database name, you can create the following six objects as shown
in Fig. 2, they are briefly described as follows,
·
Tables - a collection of data
about a specific topic, such as products or suppliers.
·
Queries - a command for viewing or
analyzing data in different ways or a result of the command.
·
Forms - a friendly interface to add a
new record
·
Reports - an object that present
data in a organized way according to your specification. Examples are telephone
bills, sales summary etc.
·
Macros - a set of one or more
actions that each performs a particular operation, such as opening a form or
printing a report. Macros can help you to automate common tasks. For example,
you can run a macro that prints a report when a user clicks a command button.
·
Module - a collection of Visual
Basic for Applications declarations and procedures that are stored together as
a unit.

Fig. 2 New Database Database1.accdb
There are three ways to create a
table:
- Use
Datasheet View, i.e. enter data directly
- Use
Design View
- Use
a Table Template
2.1 Create a Table in Datasheet View
To create a blank (empty) table in datasheet view, on the Ribbon you can:
·
Click
Create®Table in Fig. 3.
You are then given a Datasheet View with column headings ID and Add New Field across the top of
the datasheet as shown in Fig. 4. You can enter data directly into it. After
entering data and hit the Enter key, the column heading - Add New Field
automatically changes to Field1 and the next column’s heading becomes Add New
Field. At the same time, an ID number will be assigned to that row. When you
save the new datasheet, Microsoft Access will analyze your data and
automatically assign the appropriate data type and format for each field. Because the names of each field are not descriptive, you
may want to rename the fields.

Fig. 3 Ribbon for
Creating New Table
Renaming Fields:
1.
Place the cursor over the column heading you want to rename and
double click. The column heading will appear highlighted and the cursor will be
blinking (you are now in edit mode)
2.
Type the name you want to use and then press the Enter key.
3.
Repeat the first two steps for the second column, and so on.

Fig. 4: Creating a Table in Datasheet View (Renaming Fields)
As the column corresponds to the field,
the row corresponds to the record. Now we are ready to add the information. Say
that, if we are doing a database of a company, the first table we may have is Employee.
And the fields of Employee may contain SSN, LastName, FirstName, and so on.
Please refer to Fig. 5 for the example Employee table.

Fig. 5: Datasheet View (Employee Table)
Summarizing Datasheet
View

2.2 Create a Table in
Design View
In Design View you can add fields, define how
each field appears or handles data, and create a primary key. To create a blank (empty) table in design view, you can:
·
Click
Create®Table Design in Fig. 3.
You are then given a Design View
as shown in Fig. 6.

Fig. 6 Design View
In this view, we can specify
detailed properties for each field. This includes the length and type of
information used in the field. But if we were to enter data into
the table, we must use Datasheet View or Forms. The design view
for the example Employee table mentioned before will look like Fig. 7.

Fig. 7 Design View (Employee Table)
There are three columns on the
top portion of the window. The Field Name is the name of the fields. For
example, SSN, FirstName, LastName are proper field names for the Employee
table. The name for a field must follow MS Access object-naming rules[1].
The Data Type is like the domain of an attribute. It provides a list of
data types that we can choose from, including Text, Memo, Number, Date, and so
on. The Description column allows us to describe the field and it is
optional. It is always good practice to be descriptive in
your comments. This allows new users to easily understand the specifications
and meaning of your fields. Table 2 summarizes all data types available in MS
Access.
You can set up properties of
fields in the Field Properties window at the bottom half pane. Table 1 describes
all properties available for setup.
Before we save the table and
quit, we need to specify the primary key. In our Employee table, SSN
will be good for primary key. To define SSN as the primary key, click the Field
Selector as shown in Fig. 7 for the SSN field. Field Selector is the gray
bar on the left side of the Table Design grid by each field. When we click
here, the whole row appears highlighted. Then click menu Edit®Primary Key or click
the Primary Key button (i.e. the key symbol, shown in Fig. 7) on the toolbar in
design view, a key symbol will appear on the Field Selector. Save the table as
Employee. Now we have created one table.2

Table 1 Field Properties in Design View

Table 2 Data Types in MS Access
T
Summarizing
Design View[2]

2.3 Create a Table Based on a Table Template
To create a Contacts,
Tasks, Issues, Events or Assets table, you might want to start with the table
templates for these subjects that come with Office Access 2007. To choose a template
for your table from the above predefined templates you
can:
·
Click
Create®Table Templates in Fig. 3,
·
Select
one of the available templates from the dropdown list.
3. Working with Data
In this section, we will learn
how to work with existing data. The sample database file used here is
"Northwind 2007.accdb". It is a sample database comes with Microsoft
Access. You can find it in by:
- Open
MS Access; click Sample under
the category listed in the left task pane on the Getting Started with Office Access page; then click on the Northwind
2007 icon, enter the name and location on the right task pane and
click the Download button.
or
- Go to directory C:\Program
Files\Microsoft Office\Templates\1033\Access\ and double click Northwind.accdb.
Choose Object
Type on the Navigation Pane after Northwind 2007.accdb is launched, Open "Orders"
under "Tables".
3.1 Sorting
In the Datasheet View, we
can sort the records in ascending or descending orders. To sort a single
column, click anywhere in the column desired. Simply click either the Sort Ascending
button
or
Sort Descending button
on the
Ribbon. We can also click the arrow
on the right of the desired column heading and choose Sort Ascending or Sort
Descending from the popup window.


If we want to sort multiple columns,
we need to do a little more work. The two columns we want to sort by must be
adjacent to each other; the one that we want to sort by first must be to the
left of the other. Let's work with "Orders" table in Northwind
Database. Now we will try sorting by ' Shipped Date' then by 'Order
Date', we must first move 'Shipped Date' column to the left of 'Order Date'
column. Here are the steps,
- Highlight
the 'Shipped Date' column by clicking the 'Shipped Date'
column heading.
- Let
go of the mouse button and then press it again, holding it this time.
- Now
drag the 'Shipped Date' column over the 'Required Date' column.
When we get just to the left of the 'Order Date', let go of the
mouse button. Then 'Shipped Date' and 'Order Date' should
sit side by side now.
- Click
the mouse button on the 'Shipped Date' header, highlighting the
column. Holding the mouse button down, drag it over the 'Order Date' column
so that both the 'Shipped Date' and 'Order Date' columns appear highlighted.
- Click
on Sort Ascending. The sorted table is shown in Fig. 8.

Fig. 8: Northwind Database: Sort Result
3.2 Filters
By using Filter by
Selection, you tell Access that you want to see only certain records,
based on the value in the field in which the cursor currently resides. For
example, say that we want to see those orders shipped via Shipping Company B.
To do this,
1.
In the 'Ship Via' column, click a field that has "Shipping
Company B" in this field.
2.
Click the right button of mouse and select Equals
"Shipping Company B". Or, you may click Selections button
in the Ribbon and select Equals "Shipping
Company B". Only those records that were shipped via Shipping Company
B appear.
3.
Click the right button again and select "Clear filter from
Ship Via" button to remove the filter.
With Filter by Selection,
you were filtering records based on a field you selected in the datasheet, and
then selected another field in the subset to narrow it further. When using Filter
by Form, Access takes you to a different screen to specify the criteria you
want to filter with. Using Filter by Form, although more complicated,
allows you to be more specific and filter your data based on a combination of
selected values from multiple fields. To do this,
1. On the Ribbon click on Advanced Filter
Options à Filter by Form
2.
The datasheet will suddenly look as if you deleted all the
records. Refer to Fig. 9 for example. Now you can pick the fields you want to
filter and display your information.
3.
Click Ship Via field to see the drop-down list. You can use
=, >, <, >=, and <= to specify your criteria.
4.
Finally, on the Ribbon click on Toggle Filter to see the
result.

Fig. 9 Filter by Form
In the end, we will see how to
use AND and OR criterion in a filter. The AND operator
allows you to filter records based on two or more criteria. When you apply a
filter using the AND operator, only those records that meet both (or all)
criteria appear. To show how to use the AND operator, we will choose all orders
shipped before 02/12/2006 AND shipped via Shipping Company B. To do
this,
1.
On the Ribbon, click Advanced
Filter OptionsàFilter by Form to return
to the Filter by Form screen. The screen should be blank.
2.
Click Shipped Date, select 2/12/2006 and add "<" before the
date so that it looks like "<#2/12/2006#".
3.
Click Ship Via and select "Shipping Company B"
(without quotation mark).
4.
Click the Toggle Filter button on the Ribbon. Now those orders shipped before 02/12/2006 AND shipped
via Shipping Company B will appear. The resulting table contains 2 records.
Please check your answer.
To show all the orders which is
either shipped before 02/12/2006 OR shipped via Shipping Company B, you
can .
1.
On the Ribbon, click Advanced
Filter OptionsàClear All Filters.
2.
On the Ribbon, click Advanced
Filter OptionsàFilter by Form to return
to the Filter by Form screen. The screen should be blank.
3.
Click Shipped Date and select "2/16/2006"
and add "<" before
the date.
4.
Click the Or tab at the bottom of the Filter by Form screen.
5.
Click Ship Via and select
"Shipping Company B" (without quotation mark).
6.
Press Toggle Filter on
the Ribbon. Now those orders that
are either shipped before 02/12/2006 or shipped via Shipping Company B will
appear. The resulting table contains 36 records.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
CONGRATULATIONS ! You have
learned the basics of creating and manipulating tables of data
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[1] Object-naming rules are a set of specific
rules for naming Microsoft Access objects. In Microsoft Access, names can be up
to 64 characters long and can include any combination of letters, numbers,
spaces, and special characters except a period (.), an exclamation point (!),
an accent grave (`), and brackets ([ ]). Note that you also can't use leading spaces
or control characters (ASCII values 0 to 31). For information on Visual Basic
naming conventions, search the Help index for "naming conventions."
Tips
· Avoid including spaces in object names if you'll frequently
refer to the objects in expressions or Visual
Basic code.
· Avoid using extremely long
names because they are difficult to remember and refer to.
[2] You can set combination of more than two attributes as a primary
key. To do so, first highlight attributes you wish to set as primary key, and
click Primary Key button in design view.
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