Amazon Aurora provides compatibility with MySQL and PostgreSQL, but is designed to offer greater fault tolerance, recovery, and uptime than the simpler versions of those engines. It also has the capability to scale storage automatically and can survive the loss of up to two copies of data without affecting write availability, and up to three copies without affecting read availability, making it the appropriate choice for high fault tolerance requirements. MySQL and PostgreSQL are traditional database engines that can be used in AWS RDS but don't automatically provide the same level of fault tolerance and scaling capabilities as Aurora. Amazon Redshift is mainly a data warehousing service and doesn't fit the requirement for Oracle compatibility.