Load Plan Structure

1. Overview of Load Plan Structure
• A Load Plan consists of a sequence of steps, each of which can contain child steps.
• These steps can be executed in a variety of ways: conditionally, in parallel, or sequentially.
• By default, a Load Plan starts with an empty root serial step, which is mandatory and cannot be changed.
2. Types of Load Plan Steps
   Below are the different types of steps in a Load Plan and the possible child steps for each type:

1. Serial Step

• Description: This step defines a sequential execution of its child steps. A child step is executed only after the previous one completes.
• Possible Child Steps:
• Serial step
• Parallel step
• Run Scenario step
• Case step

2. Parallel Step

• Description: This step defines a parallel execution of its child steps. All child steps start immediately in their order of priority.
• Possible Child Steps:
• Serial step
• Parallel step
• Run Scenario step
• Case step

3. Run Scenario Step

• Description: This step launches the execution of a scenario (such as a package or procedure).
• Note: This type of step cannot have any child steps.

4. Case Step

• Description: This step allows for conditional branching based on a variable's value. It contains the following steps:
• When step: Executes based on a condition.
• Else step: Executes if no When step condition is satisfied.
• Possible Child Steps:
• Of a Case Step: When step, Else step
• Of a When Step: Serial step, Parallel step, Run Scenario step, Case step
• Of an Else Step: Serial step, Parallel step, Run Scenario step, Case step

5. Exception Step

• Description: This step defines actions to take when an exception occurs in the associated step in the step hierarchy. The same exception step can be attached to multiple steps.
• Possible Child Steps:
• Serial step
• Parallel step
• Run Scenario step
• Case step
2. Example of Load Plan Execution
• In a sample Load Plan for loading a data warehouse:
• Dimensions are loaded in parallel:
• LOAD_TIME_DIM, LOAD_PRODUCT_DIM, LOAD_CUSTOMER_DIM scenarios are executed in parallel.
• Based on the value of ODI_VAR_SESS1, either the CUST_NORTH or CUST_SOUTH scenario is executed.
• The Geographical Dimension consists of a sequence of three scenarios: LOAD_GEO_ZONE_DIM, LOAD_COUNTRIES_DIM, and LOAD_CITIES_DIM.
• After the dimensions are loaded, the two fact tables (LOAD_SALES_FACT and LOAD_MARKETING_FACT) are loaded in parallel.