If there exists primary and foreign key information in your data base and you choose to include that in your metadata import (it's default setting is on) then relationships between your tables should exist.
If not, then you can create them.
Select the two query subjects you want to join and choose create relationship from the context menu.
This will open the relationship editor. You can then define what keys and the cardinality of the relationship between the tables.

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IAN HENDERSON
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