Joining Tables

A relational database typically consists of data stored in many different tables. Joining tables allows you to obtain information from more than one table at one time and enables you to choose various data subsets of the joined tables. In a join, the currently selected table is the Master Table and the table it is joined to is the Lookup Table. The currently selected table name appears after the FROM keyword in the SQL Select Statement text box.

A table join relationship can be established in the following way:

The join is defined in Visual SQL Query Builder dialog. The table currently selected is the Master Table, and the second table selected is the Lookup Table. The join is completed visually by left clicking a field in the Master Table, holding the left mouse button down, and dragging the field in the Lookup Table. A join graphic, a line with two end nodes, is generated showing the fields that have been joined.

Note: To delete the join, click one of the join graphic nodes, and press Delete.

Note: Insert, Update, and Delete database operations are not supported for joined tables.

The Where tab page can be used to create compound Where clauses with joined tables. For example: