Join Conditions
When you include more than one table in a query you must
specify how the tables will be linked. Those specifications are
called the join conditions. From the diagram interface, there are
several ways to specify the join conditions:
- When you add a table to the query, the Join Tables window and
the Join Columns windows open automatically in sequence. You use
these windows to specify the type of join will be applied to the
tables and what columns will joined. These windows are the same
as those used to specify join conditions when you creating queries
using the prompted interface. Refer to Join Conditions for more information on the fields in these windows.
- Use the drag and drop method. Select a column from one table
and drag it to a column in another table. A connecting line is
drawn from the column in the first table to the column in the second
table.
- Select Add --> Join Conditions.
The Join Tables window opens followed by the Join Columns window.
These windows are the same as those used to specify join conditions
when you creating queries using the prompted interface. Refer to Join Conditions for more information on the fields
in these windows.
You can change the join conditions or delete a join condition
by right clicking on the line that joins the table diagrams in the
top section of the window. A context menu opens offering you two
choices:
- Select Remove join to remove the join condition that
connects the two tables. You must have a least one join condition
to link the tables.
- Select Change join to change the join condition. The
Join Tables window opens., followed by the Join Columns window where
you can make changes to the join conditions.
