Operation Manual

Step 10: Close, save, and name the query
My suggestion for a name is Fuel Economy.
1) Click the Save icon.
2) Name the query.
3) Close the query.
4) Save the database file.
There are obviously other calculations that can be made in this query such as cost per distance
traveled and how much of the cost belongs to each of the payment types.
Note
To fully use queries requires a knowledge of set operations (unions, intersections, and,
or, complements, or any combinations of these). Having a copy of the HSQLDB User
Guide, available from http://hsqldb.org/doc/guide/guide.pdf, is also extremely useful.
Creating reports
Reports provide information found in the database arranged in a useful way. In this respect, they
are similar to queries. They are different in that they are designed to be distributed to people.
Queries are only designed to answer a question about the database. Reports are generated from
the database’s tables, views, or queries.
All reports are based upon a single table, view, or query, so you need first to decide what fields you
want to use in the report. If you want to use fields from different tables, you must first combine
these fields in a single query or view. Then you can create a report from this.
For example, a report on vacation expenses includes both fuel costs and meal costs. These values
are contained in fields of two different tables: Vacations and Fuel. So this report requires you to
create a query or view.
Caution
Dynamic reports update only the data that is changed or added to a table or query.
They do not show any modifications made to the table or query itself. For example,
after creating the report below, open the fuel economy query created in the previous
section. For the "End-Reading".”Odometer” – “Fuel.”Odometer” column, change the
number 1 to the number 3. The report will be identical before and after you make the
change. But if you add more data to the query and run the report again, it will contain
the new data. However, all data will be based upon "End-Reading".”Odometer” –
“Fuel.”Odometer” having the value 1. No data will be present in the report for which
"End-Reading".”Odometer” – “Fuel.”Odometer” has the value 3.
Creating a report: Example
We will create a report on vacation expenses. Certain questions need to be asked before creating
the report.
• What information do we want in the report?
• How do we want the information arranged?
• What fields are required to provide this information?
• Will a query or view have to be created because these fields are in different tables?
• Are any calculations required in the data before being added to the report?
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