Need to verify if the database is encrypted per customer security policies.
CDW 6.0 bundles PostgreSQL 9.5 and installs it mostly with default settings. PostgreSQL has documented several Encryption Options.
https://www.postgresql.org/docs/9.5/encryption-options.html
Note that CDW uses the database to log statistics, manage the TCQ and store the list of messages.
It does not store sensitive data, like passwords, or configuration in the database.