DBML is a text format to represent the database in the database diagram. Basically, it describes the tables, their columns, and the table relations (based on table foreign keys). There are desktop and online tools which use the DBML text as input and produce graphical db diagrams as output.

To export your database structure to DBML, open the needed database and choose Export | Export Structure to DBML... menu.

You can choose which schemata (if supported by your database) and tables to export.

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