SonarQube upgrade to 7.3 version from 6.7.5v

[NicoB (Nicolas Bontoux)]

I would suggest first reviewing existing ‘unicity constraint’ errors reported here, couple of discussions on this topic. For example:

Upgrade of SonarQube from version 6.3 to 6.7.5 fails at step #1641

Hello, Unicity constraint violation during a DB migration does indicate a potential problem with the dataset itself. Either during this upgrade an instance was connected to the database and changing the dataset, or you are working with a dump done in hot backup mode. Anyway, you need to check that no instance is connected to the db while performing the migration or to get a dump done in cold backup mode. Greetings, Alex.