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First log into the PostgreSQL prompt as explain in PostgreSQL on Ubuntu.
Create the confluence database admin account,CREATE ROLE confluencedbuser LOGIN ENCRYPTED PASSWORD 'putYourPasswordHere'
NOINHERIT
VALID UNTIL 'infinity';
COMMENT ON ROLE confluencedbuser IS 'Account used by the Confluence application.';
Create the database.
CREATE DATABASE confluencedb
WITH ENCODING='UTF8'
OWNER=confluencedbuser
CONNECTION LIMIT=-1;
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