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ERD Tool

The Entity-Relationship Diagram (ERD) tool is a database design tool that provides a graphical representation of database tables, columns, and inter-relationships. ERD can give sufficient information for the database administrator to follow when developing and maintaining the database. The ERD Tool allows you to:

  • Design and visualize the database tables and their relationships.

  • Add notes to the diagram.

  • Auto-align the tables and links for cleaner visualization.

  • Save the diagram and open it later to continue working on it.

  • Generate ready to run SQL from the database design.

  • Generate the database diagram for an existing database.

  • Drag and drop tables from object explorer to the diagram.

ERD tool window

You can open multiple copies of the ERD tool in individual tabs simultaneously. You can also generate an ERD from a database, schema or a table.

  • The ERD for database will fetch all the tables from all the schemas of the database and plot them with foreign key links.

  • The ERD for schema will fetch all the tables from a schema and plot them with foreign key links. If any table refers to a table in another schema, then that link/foreign key will be removed.

  • The ERD for table will fetch all the tables linked directly or indirectly to mentioned table. You can change the depth of traversal from Preferences.


The ERD Tool toolbar uses context-sensitive icons that provide shortcuts to frequently performed tasks. The option is enabled for the highlighted icon and is disabled for the grayed-out icon.

ERD tool toolbar

Hover over an icon on Toolbar to display a tooltip that describes the icon’s functionality.

File Options




Open File

Click the Open File icon to load a previously saved diagram.

Cmd/Ctrl + O


Click the Save icon to perform a quick-save of a previously saved diagram, or to save the diagram to a file.

Cmd/Ctrl + S

Save as

Click the Save As to open a new browser dialog and specify a new location to save the diagram. You need to click the down arrow beside the save button to see Save As.

Ctrl + Shift + S

Export Options




Generate SQL

Click the Generate SQL icon to generate the DDL SQL for the diagram and open a query tool with the generated SQL ready for execution. You can select the option With DROP Table if you wish to have DROP Table DDL statements before each CREATE Table DDL. You can see the option by clicking the down arrow beside the SQL button.

Option/Alt + Ctrl + S

Download image

Click the Download image icon to save the ERD diagram in a image formate

Option/Alt + Ctrl + I

Editing Options




Add table

Click this button to add a new table to the diagram. On clicking, this will open a table dialog where you can put the table details.

Option/Alt + Ctrl + A

Edit table

Click this button to edit a table on the diagram. On clicking, this will open a table dialog where you can change table details. This will enable when a table is selected.

Option/Alt + Ctrl + E

Clone table

Click this button to clone the complete table structure, name it with a auto generated name and put it in the diagram.

Option/Alt + Ctrl + C

Drop table/link

You can drop a table or link using this button. You need to select a table or link and click on this button to drop it.

Option/Alt + Ctrl + D

Table Relationship Options





Click this button to open a one-to-many relationship dialog to add a relationship between the two tables. The selected table becomes the referencing table and will have the many endpoint of the link.

Option/Alt + Ctrl + O


Click this button to open a many-to-many relationship dialog to add a relationship between the two tables. This option will create a new table based on the selected columns for the two relating tables and link them.

Option/Alt + Ctrl + M

Node Color Options



Fill Color

Use Fill Color to change the background color of a table node. This is helpful if you want to identify a of group tables. Once set, all the newly added tables will take the same color.

Text Color

Use Text Color to change the text color of a table node based on the fill color to make text easily readable.

Utility Options




Add/Edit note

Click this button to make notes on tables nodes while designing the database.

Option/Alt + Ctrl + N

Auto align

Click this button to auto align all tables and links to make it look more cleaner.

Option/Alt + Ctrl + L

Show details

Click this button to toggle the column details visibility. It allows you to show few or more column details.

Option/Alt + Shift + D

Cardinality Notation

Change the cardinality notation format used to present relationship links. Options available are - Crow’s Foot Notation and Chen Notation.

Zoom Options




Zoom to fit

Click this button to zoom in/out automatically and fit all the tables to the view.

Option/Alt + Shift + F

Zoom in

Click this button to zoom in the diagram.

Option/Alt + Shift + “+”

Zoom out

Click this button to zoom out the diagram.

Option/Alt + Shift + “-”

Table Dialog

ERD tool table dialog

The table dialog allows you to:

  • Change the table structure details.

  • It can be used edit an existing table or add a new one.

  • Refer table dialog for information on different fields.

Table Node

ERD tool table node

The table node shows table details in a graphical representation:

  • The top bar has a details toggle button that is used to toggle column details visibility. There is also a note button that is visible only if there is some note added. you can click on this button to quickly change the note.

  • The first row shows the schema name of the table. Eg. public in above image.

  • The second row shows the table name. Eg. users in above image.

  • All other rows below the table name are the columns of the table along with data type. If the column is a primary key then it will have lock key icon eg. id is the primary key in above image. Otherwise, it will have column icon.

  • you can click on the node and drag to move on the canvas.

  • Upon double click on the table node or by clicking the edit button from the toolbar, the table dialog opens where you can change the table details. Refer table dialog for information on different fields.

The Table Notes

ERD tool table note
  • You can use the notes popup to mark some notes while designing the database.

  • You open the pop-up using the toolbar note button.

  • If some note is added to a table then it will have notes button on the table node. You can click on the button to check/update notes.