Overview
If the system is configured with external databases, connecting the external database is required every time you start a project.
If you have directly modified the account and password of the external database, the project will fail to connect to the external database, resulting in a startup failure. This article briefly introduces how to modify the account and password of external databases correctly and provides solutions to incorrect modification.
Modification Method
This article provides two methods for modifying the account and the password of the external database.
Method 1: Requiring No Migration

This method is only valid for standalone projects.
In a cluster environment, close all nodes and start one node to modify the password.
After modification, copy the db.properties file and paste it to unmodified nodes, then shut down all nodes in the cluster and restart them.
Start the project. Log in to the decision-making system, and choose System Management > System Setting > General > External Database > Configured, as shown in the figure below:
Make sure that the External Database Configuration page is open.
Modify the account and the password of the database as needed.
Enter the new account and password on the External Database Configuration page, do not tick Migrate Data to Database to be Enabled, and click Enable New Database.
Method 2: Temporary Migration
Prepare an empty database that is not related to the external database to be modified.
Migrate the external database to the new database following the corresponding instructions. Remember to tick Migrate Data to Database to be Enabled.
Modify the account and password of the external database.
Migrate the external database back to the original database again after modification. Remember to tick Migrate Data to Database to be Enabled.
Solutions
If you have modified the account and the password of the external database without following the above steps, the project may fail to be started and you will automatically go to the server deployment wizard page, on which it will prompt Database Connection Exception. External Database Connection Error, as shown in the figure below:
This chapter will briefly introduce the solutions.
Method 1: Resetting Account and Password
Contact the database administrator to reset the account and the password of the external database.
Modify the account and password of the external database following the instructions in the Modification Method section after you can normally start the project.
Method 2: Reconfiguring External Database
Reconfigure the external database on the server deployment wizard page.