Question
How to change a PostgreSQL admin password in Plesk?
Answer
Changing the password via Plesk
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Go to Tools & Settings > Database Servers > PostgreSQL > localhost (or another corresponding hostname) next to PostgreSQL.

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Specify a new password and click OK.

 
Changing the password via a command-line interface
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Connect to a Plesk server via SSH.
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Run the following command to change the password:
# plesk bin database-server --update-server localhost:5432 -type postgresql -passwd '*****'
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where ***** is a new PostgreSQL admin password.
 
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