DAC Repository Objects

About DAC Repository Objects Held in Source System Containers

All DAC repository objects are associated with a source system container.

For more information about source system containers, see "About Source System Containers" and "About Object Ownership in DAC".

DAC repository stores application objects in a hierarchical framework that defines a data warehouse application.

DAC enables you to view the repository application objects based on the source system container you specify.

The source system container holds the metadata that corresponds to the source system with which you are  working.

A data warehouse application includes but is not limited to the following repository objects:

 Subject areas.

1)   A logical grouping of tables related to a particular subject or

         Application context.

2)   It also includes the tasks that are associated with the tables, as well as the tasks required to load the tables.

3)   Subject areas are assigned to execution plans, which can be scheduled for full or incremental loads.

Tables.

Physical database tables defined in the database schema.

 Can be transactional database tables or data warehouse tables.

 Table types can be fact, dimension, hierarchy, aggregate, and so on, as well as flat files that can be sources or targets.

Indexes.

 Physical database indexes to be defined in the database schema either to better the performance of the ETL processes or the queries for reporting purposes.

Tasks.

A unit of work for loading one or more tables.

A task comprises the following:

 Source and target tables, phase, execution type, truncate properties, and commands for full or incremental loads.

 When you assemble a subject area, DAC automatically assigns tasks to it.

Tasks that are automatically assigned to the subject area by DAC are indicated by the Autogenerated flag in the Tasks subtab of the Subject Areas tab.

Task groups.

 A group of tasks that you define because you want to impose a

Specific order of execution. A task group is considered to be a "special task."

Execution plans.

A data transformation plan defined on subject areas that needs to be transformed at certain frequencies of time.

 An execution plan is defined based on business requirements for when the data warehouse needs to be loaded.

 An execution plan comprises the following:

 Ordered tasks,

Indexes,

 Tags,

Parameters,

Source system folders,

And

Phases

Schedules.

A schedule specifies when and how often an execution plan runs.

An execution plan can be scheduled for different frequencies or recurrences by defining multiple schedules.