Microsoft Office Tutorials and References
In Depth Information
Section 6: Selecting data using queries
6
Selecting data
using queries
In this section:
Queries are where a database can offer a real benefit over a
spread■ Selecting all or individual columns
from one or more tables
Joining tables to see unmatched or
missing records
Filtering by single and multiple
combinations of choices
Adding calculations with the
expression builder
Returning top records and
eliminating duplicate
Creating a summary calculation
Prompting to filter data with
parameters
Turning rows into columns with a
crosstab query
Working with queries that use other
queries
sheet because they allow you to construct sophisticated, updatable
presentations of your data. These can vary in complexity from a simple
filtered list based on a single table to more complicated presentations of
summarized information involving many tables of data. Remember that a
database encourages you to split your data into separate tables to reduce
duplication of information when you are entering data, at the expense of
having that data in several places. You will see that queries lie at the very
heart of a database and allow you to reassemble the data from the
different tables into a single view with greater flexibility than if the data were in
one list.
The power of queries increases as you gain more experience with Access.
For example, layering one query on top of another allows you to break
down a complex problem into several simple steps. A query can
display data both from tables and from other queries. Queries can also be
parameterized to prompt users to enter filtering criteria, and they can be
extended so that they are driven by selections that you make in forms.
(See “Linking a form to a query” on page 224.)
Search JabSto ::




Custom Search