If you were redirected while trying to reach the PuppetDB docs at puppet.com/docs/puppetdb, the version you were trying to reach is no longer maintained.
For the most recent PuppetDB docs, see puppet.com/docs/puppetdb/latest. For a list of the current maintained versions of open source Puppet and its components, see the most recent Puppet version information. For a list of supported Puppet Enterprise versions, see the Puppet Enterprise lifecycle.
If you need docs for an older version of PuppetDB, you may be able to find it by switching to the relevant branch of this repository.