Join Line Tab, Properties Window

Visual Database Tools

Visual Database Tools

Join Line Tab, Properties Window

Specifies options for the joining of tables in a query.

By default, related tables are joined using an inner join that creates a result set based on rows containing matching information in the join columns. By setting options in the Join Line tab, you can specify a join based on a different operator, and you can specify an outer join.

For more information about joining tables, see Querying Using Multiple Tables.

Options

Table

The names of the tables involved in the join. You cannot change the names of the tables here — this information is displayed for information only.

Column

The names of the columns used for joining the tables. The operator in the Operator list specifies the relationship between the data in the columns. You cannot change the names of the columns here — this information is displayed for information only.

Operator

Specifies the operator used to relate the join columns. To specify an operator other than equal (=), select it from the list. When you close the dialog box, the operator you selected will appear in the diamond graphic of the join line, as in the following:

Include rows

Specifies whether unmatched rows appear in the Results pane.

All rows from <table1>

Specifies that all the rows from the left table appear in the output, even if there are no corresponding matches in the right table. Columns with no matching data in the right table appear as null. Choosing this option is equivalent to specifying LEFT OUTER JOIN in the SQL statement.

All rows from <table2>

Specifies that all the rows from the right table appear in the output, even if there are no corresponding matches in the left table. Columns with no matching data in the left table appear as null. Choosing this option is equivalent to specifying RIGHT OUTER JOIN in the SQL statement.

Selecting both All rows from <table1> and All rows from <table2> is equivalent to specifying FULL OUTER JOIN in the SQL statement.

When you select an option to create an outer join, the diamond graphic in the join line changes to indicate that the join is a left outer, right outer, or full outer join.

Note   The words "left" and "right" do not necessarily correspond to the position of tables in the Diagram pane. "Left" refers to the table whose name appears to the left of the keyword JOIN in the SQL statement, and "right" refers to the table whose name appears to the right of the JOIN keyword. If you move tables in the Diagram pane, you do not change which table is considered left or right.

See Also

Query Designer Properties Pages