Persistence Layer

Zed’s persistence layer is the owner of the schema, entities and queries. This layer knows the database structure and holds the connection to it.

Integrated Technologies

Propel Fast and simple ORM Framework MySQL or PostgreSQL Both databases are supported

Persistence Layer Elements:

Query container

A query container holds all the queries in the current module.


An entity represents a single row from the database.


Query objects provide an object-oriented API for writing database queries.

Schema definition

Xml-files that define the database schema for the related module.

Abstract factory

The factory is used to instantiate query objects.

The following diagram shows how the elements interact:

Inside The Persistence Layer


See also: