Entity Relationship Maps

    Even the most experienced database professionals are known to feel a little anxious when peering into an unfamiliar database. Hopefully, they inspect to see how the data is normalized and how the various tables are combined to answer complex queries.  Entity Relationship Maps (ERM) provide a visual overview of how tables are related and can document the structure of the data.

    The Community Edition of DBeaver can provide an ERM easily.  First, connect to the database. Right-click on the 'Tables' and then select 'View Diagram'.


The ERM is then displayed.



And it gets better! If you are not sure how two tables are joined? Click on the link between the tables, and the names of the columns you will want to use in your JOIN statement are highlighted.



Conclusion

    Exploring an unfamiliar database can be daunting. But Entity Relationship Maps provide a way to navigate the territory. And DBeaver is a fantastic tool for working with databases.


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