SaaS providers that offer managed Ed-Fi ODS / API may find it useful to partition by customers using an Instance Identifier and the School Year; this way each Instance/Year combination gets a separate database providing the following benefits:

Isolation

Data is isolated by Instance and by Year so the data will not leak between multiple Instances nor Years. API security and client access setup is isolated by Instance. 

Data archival

This strategy allows archival/deletion of the data for a customer (single or multiple Years) when they no longer require access to it.

Scaling

When combined with multi-server deployment (one server per Instance), each set of databases can be scaled (CPU/RAM/etc.) individually.

Configuration 

Routing

When enabled, the base URI follows /{api_area}/{version}/{instance}/{year} pattern. 'Instance' must match the regex ^[A-Za-z0-9-]+$ (i.e. alphanumerics and dashes, a GUID for example). See API Routes for details.

How to enable

The ODS / API can be configured for instance-year-specific configuration through the following steps:

• Update ApiSettings:Mode key in the appsettings.json of the EdFi.Ods.WebApi project to: "Mode": "InstanceYearSpecific"
• Within EdFi_Ods connection string, add the {0} template string to the database name which will be replaced at runtime with the appropriate Instance and Year, for example:

server=(local);trusted_connection=True;database=EdFi_{0};Application Name=EdFi.Ods.WebApi

Assuming that Instance = my-instance and Year = 2021 in the request URL, database name will get translated to EdFi_Ods_my-instance_2021 at runtime.

• Within EdFi_Admin connection string, add the {0} template string to the database name, for example:

server=(local);trusted_connection=True;database=EdFi_{0};Application Name=EdFi.Ods.WebApi

        Assuming that Instance = my-instance and Year = 2021 in the request URL, database name will get translated to EdFi_Admin_my-instance at runtime. Notice that the Admin DB is not partitioned by Year.

• Within EdFi_Security connection string, add the {0} template string to the database name, for example:

server=(local);trusted_connection=True;database=EdFi_{0};Application Name=EdFi.Ods.WebApi

Assuming that Instance = my-instance and Year = 2021 in the request URL, database name will get translated to EdFi_Security_my-instance at runtime. Notice that the Security DB is not partitioned by Year.

Limitations

• There is no database deployment support for this strategy yet. So initdev will not create databases with the corresponding database names. 
• Since only the database name is interpolated in the connection strings, the databases must reside in the same server.
• SwaggerUI is not available yet for this strategy. See ODS-4978 for details.

See the Extensibility & Customization section for information on using Instance-Year-Specific configuration as a facet of a partitioning strategy.