Ozds.Data

This project contains all entities and queries for the database. The entities are kept in the Entities namespace and queries are functions in the OzdsDbClient class. The class is partial and it is divided into conceptually similar files (ie. all queries for meters are in the OzdsDbClientMeters.cs file).

Schema

The schema is generated using mermerd when it is migrated to the latest migration generated by dotnet ef.

Ozds.Data.Entities

Contains entities that are used to represent tables in the database.

There are a couple of marker interfaces that are used to implement certain functionality or interceptors in Ozds.Business:

• Readonly: marker interface used to implement read-only entities by throwing exceptions on mutations

• Aggregate: marker interface used to implement measurement aggregation. For now measurements are aggregated in quarter-hourly, daily and monthly intervals.

• Measurement: marker interface used to implement aggregations over measurements.

Apart from the marker interfaces, entities can be grouped in a few class hierarchies. Virtual properties on entity classes are navigation properties to other entities they have a relationship with and are not kept in the database. These hierarchies make it easier to group entities that have similar mapping to database tables:

• Auditable: entities that can be audited. These entities also have soft delete functionality implemented via interceptors.

• Event: entities that represent events.

• Measurements: entities that represent measurements. Concrete measurement types have navigation properties to specific meter types.

• Aggregates: entities that represent aggregated measurements. The timestamp is the start of the interval and the count is the number of measurements in that interval. Concrete aggregate types have navigation properties to specific meter types.

• Calculations: entities that represent calculations. Calculations that don't have a issuer are issued automatically by the server.

• Invoices: entities that represent invoices.

Ozds.Data.Migrations

This namespace contains generated migrations for the database. The migrations are generated using dotnet ef and are kept in the Migrations directory.