Docs › Server and objects

ER diagrams and dependencies

Draw a database's tables with their keys and relationships, export the diagram, and see what uses an object before you change it.

#ER diagrams

Right-click a database ▸ ER Diagram, or a table ▸ Show in ER Diagram for that table and its neighbours. The diagram opens in a tab:

• Each table lists its columns with their types and nullability; 🔑 marks primary-key columns, and foreign keys are drawn as lines with crow's feet on the many side.
• Long tables fold their remaining columns (+ 10 more columns).
• Zoom with the toolbar or a pinch, drag tables to arrange them (the layout is remembered per database), and Reset Layout starts again.
• Double-click a table to script it and open its data; right-click for Find Usages, Dependencies and its neighbourhood.
• Export ▾ saves the diagram as a PNG or SVG image, for a design document or a wiki.

#Find usages and dependencies

Before you change or drop something, see what it touches. Right-click any object in Object Explorer (or SQL Search):

• Find Usages lists everything that uses it: Usages of dbo.Orders, such as the views, procedures, functions and triggers that read it;
• Dependencies lists what it uses: Dependencies of dbo.usp_PlaceOrder.

Each opens a tab showing the result as a tree grouped by type, or a left-to-right graph with the object highlighted. Objects in other databases show their three-part names, and cycles are drawn dashed. Click to select, double-click to open Script as CREATE, and Reveal in Explorer finds the object in the tree.

-- Before dropping a column, check what reads it:
-- Object Explorer ▸ dbo.Orders ▸ Find Usages
ALTER TABLE dbo.Orders DROP COLUMN ShipVia;