How to get ERD diagram for an existing database?

Question

I have a PostgreSQL database. I want to get its ERD. How can I do so?

Answer 1

You can use dbeaver to do this. It allows you to export the ER diagram as png/svg etc.

DBeaver - https://dbeaver.io/

Double click on a schema (eg, Schemas->public->Tables) and open the "ER Diagram" tab (next to "Properties" tab)

Answer 2

1. Open MySQL Workbench. In the home screen click 'Create EER Model From Existing Database'. We are doing this for the case that we have already made the data base and now we want to make an ER diagram of that database.

2. Then you will see the 'Reverse Engineer Database' dialouge. Here if you are asked for the password, provided the admin password. Do not get confused here with the windows password. Here you need to provide the MySQL admin password. Then click on Next.

3. In the next dialouge box, you'll see that the connection to DBMS is started and schema is revrieved from Database. Go next.

4. Now Select the Schema you created earlier. It is the table you want to create the ER diagram of.

5. Click Next and go to Select Objects menu. Here you can click on 'Show Filter' to use the selected Table Objects in the diagram. You can both add and remove tables here.Then click on Execute.

6.When you go Next and Finish, the required ER diagram is on the screen.

Answer 3

pgModeler can generate nice ER diagram from PostgreSQL databases.

• https://pgmodeler.io/
• License: GPLv3

It seems there is no manual, but it is easy enough without manual. It's QT application. AFAIK, Fedora and Ubuntu has package. (pgmodeler)

In the latest version of pgModeler (0.9.1) the trial version allows you to create ERD (the design button is not disabled). To do so:

1. Click Design button to first create an empty 'design model'
2. Then click on Import and connect to the server and database you want (unless you already set that up in Manage, in which case all your databases will be available to select in step 3)
3. Import all objects (it will warn that you are importing to the current model, which is fine since it is empty).
4. Now switch back to the Design tab to see your ERD.

Answer 4

I use DrawERD for ERD & DB doc. https://drawerd.com

Answer 5

You can generate ER diagram from PgAdmin.

1. Open PgAdmin
2. Right click on any table and select statement and it will show two window one is query other is graphical window so you can add the table which you want to generate the diagram.
3. To save go to save as and select Graphical Query (image)

Answer 6

Another option is use Oracle SQL Developer. Two steps as below:

(1) First of all, you need to connect SQL Developer to your PostgreSQL database.

(2) Then you can generate an entity-relationship (ER) diagram using SQL Developer