For plesk version 10 and above
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1. Log into plesk control panel.
2. Select the desired domain from "Domains" list.
3. Select "Databases" option from "Websites & Domain" tab.
4. Click on "Add new Database" option from "Databases" tab.
5. Enter the database name and select the database server.
6. Enable the check box "Create a new database user" option.
(Note: If no database users are assigned to database, it will not be accessible)
7. Enter valid user name and password.
8. Click "OK" button.
For plesk version 9
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1. Log into plesk control panel.
2. Select the particular domain from "Domains" list.
3. Select "Databases" option from "Applications & Services" tab.
4. Click on "Add new Database" option.
5. Provide valid database name.
6. Select desired "Database server" and type( Eg:Mysql,postgresql).
7. Click on "OK" button.
To create the database user
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1. Select the desired domain from from "Domains" list.
2. Select "Databases" option from "Applications & Services" tab.
3. Select the desired database.
4. Click on "Add New Database User" option from "Tools" tab.
5. Enter valid user name and password.
6. Click "OK" button.