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Microsoft Access Forms
By: Dan D'Urso
Published: October 2002
Like many desktop database
application development tools,
Microsoft Access has very robust
facilities for creating forms. For
reporting applications you will use
yourself you may not need many
forms. But if you are setting up a
database for someone else to use
you will want to create a set of
forms for data entry, report
selection, etc.
The purpose of this article is not
to present a tutorial on how to
design a form. There are many good
sources of information on that.
Rather, I want to focus on the
effect that table relationships and
queries have on the basic structure
of the forms. Along the way we'll
see just how much of the legwork
can be done for you by the Access
form wizard, especially if you have
properly designed your tables,
queries and relationships. So let's
cover a few basics first.
Background
Bound vs Unbound Forms
Access can create two types of
forms: bound and unbound. A bound
form is connected to a table or
query via a record source property.
An unbound form has no record
source. It can be used to collect
criteria, such as a date range, for
reports, searches, etc. This
article focuses on bound forms.
Data Sources
Each form has one (and only one)
record source. This is an important
point since it would seemingly
imply that a form can be used to
update only one table. But this is
not so. A query which draws from
more than one table can also be
used. If it is updatable then you
can update multiple tables via one
form (more about this later). In
the example below we are using a
work_orders table. It could just as
easily have been a query.

Subforms
Access has the ability to create
subforms. These are similar to
regular forms and have their own
record source. Once created they
can be embedded in or linked to a
main form and Access will
automatically maintain the
relationship between the data in
the two forms.
The remainder of this article will
discuss form creation in light of
existing tables, relationships and
queries. We'll start with tables
and then delve into using queries.
Simple Data Entry Forms
You did do a thorough job of
setting your field properties,
didn't you? If not go back and
finish this job now. The Form
Wizard will use the caption
property to generate the field
labels. If you've set these already
then you will automatically get
meaningful labels on your forms
with no further work.
A simple data entry form is all
that's needed to update many of the
tables in your database. For
example customers, suppliers,
vendors, parts, locations, etc. You
should have a data entry form for
each of these. It won't handle your
transactions or fancier displays
but we'll get to that later. Here's
a real simple form for updating
employee information for a sample
database.
more
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