The premise of this document is to provide reader with ideas on how to manage a growing number of reference databases as teams adopt Datical.
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Oracle 12c has the concept of pluggable databases (PDBs). A PDB is a portable collection of schemas, schema objects, and non-schema objects that appear to an Oracle Net client as a separate database. One or more PDBs together are called a container database (CDB).
Because each PDB is a separate database, you can configure all Reference Databases as PDBs on a single Oracle 12c instance. The number of PDBs (hence number Reference Databases) per Oracle 12 instance would be dictated by the size of each Reference Database (size depends on number of objects in the database and the amount of data needed in the database).
Best Practices for High Availability
Because possibly large number of databases will be running on few servers, it would be necessary to consider High Availability options for each database. The key consideration here is for SQL Server instances. The out-of-the-box configuration for SQL Server requires elevated privileges which requires SQL Server instances to be configured in single user mode. However, a custom, non-elevated setup can be used which can work with SQL Server instances configured in Availability Groups (AG).