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Enhanced E-R Diagram

NineData Enhanced ER Diagram visualizes logical relationships between tables and fields in a database. It analyzes physical foreign keys, metadata matches, and uploaded SQL association queries to help you understand database structure and dependencies more quickly.

Background Information​

Traditional ER diagrams show physical foreign key relationships, but they may miss relationships that exist only in business logic. NineData's Logical ER Diagram supplements physical foreign keys with intelligent identification, metadata analysis, and manual correction, providing a relationship view that is closer to real application logic.

Usage Scenarios​

  • Understand complex database structures: When a database has many tables or complex relationships, use the Logical ER Diagram to quickly understand how data objects are connected.

  • Plan business system upgrades or migrations: Before a system upgrade or cross-platform migration, analyze data dependency chains to reduce omissions and errors.

  • Support data quality and lineage management: Identify field dependencies, trace source data, and support metadata governance.

Prerequisites​

  • The target data source is MySQL or OceanBase MySQL.

  • When the database contains many tables, for example 1,000 tables, the initial Logical ER Diagram build may take a long time.

  • Logical relationships come from automatic identification and manual correction. Review them against the actual business model before relying on them for design or migration decisions.

  • Only databases and tables that you are authorized to access under the current data source are displayed.

Procedure​

  1. Open the target data source in the SQL Console.

  2. Click the er icon. If no target database is selected in the SQL Console, a database selection window appears. Select the database for which you want to view the Logical ER Diagram, then click OK.

  3. On the Build an enhanced E-R diagram page, choose whether to upload an SQL file that contains business association queries. To upload a file, select the file and click Upload files and build. The system parses multi-table relationships in the file to improve model accuracy. To build without a file, click Direct Build.

  4. When you open the Logical ER Diagram for the first time, the system mines table relationships. Wait for the build to finish, then refresh the page to view the diagram.

    tip

    Build time depends on the number of tables in the current database and the complexity of the relationships.

  5. Use the following controls to inspect and adjust the Logical ER Diagram.

    Functional Module
    		Operation Description
    Canvas Operation
    • Zoom Canvas: Hover over a blank area of the canvas, then use the mouse wheel to zoom in or out. You can also click the zoomin Zoom In, zoomout Zoom Out, or autofit Auto Fit icon in the toolbar.
    • Drag Canvas: Click and hold a blank area of the canvas to drag the canvas.
    • Full Screen Display: The Logical ER Diagram opens in full-screen mode by default. Click Exit in the toolbar to switch the diagram to drawer mode.
    Search and Highlight LocationEnter a table name in the search box to find the target table. The matching table name is highlighted. Fuzzy search is also supported.
    View Table and Field Details
    • Hover over a table object to view the table name and comments.
    • Hover over a field object to view the field name, comments, type, length, default value, and non-null attribute.
    Table ModeClick the table_mode icon to switch to table mode. Table mode displays field dependencies in table form. In table mode, you can correct or remove field dependencies.
    • View Data Dependencies: By default, table mode displays fields with dependencies. Click All to switch to all fields.
    • Search Dependency Relationships: Enter the table or field name in Source Table, Reference Table, Source Table Column, or Reference Column, then click Search. Fuzzy matching and exact matching are supported.
    RebuildClick Rebuild in the toolbar to reconstruct the logical relationships for the entire target database. During reconstruction, the page displays progress as a percentage. Click Stop the build and close to cancel the reconstruction and close the Logical ER Diagram window.

Result​

The Logical ER Diagram displays table-level and field-level relationships for the selected database. Use it to validate dependencies before schema changes, migrations, or metadata governance work.