 On one end of the spectrum, a system with minimal automation will require significant experienced resources to manage; perhaps 5-10 databases per DBA.Alternatively an organization might choose to automate a significant amount of the work that could be done manually therefore reducing the skills required to perform tasks.As automation increases, the personnel needs of the organization splits into highly skilled workers to create and manage the automation and a group of lower skilled "line" DBAs who simply execute the automation.