About ETL Phases

Oracle BI Applications ETL processes include these phases: SDS, Health Check, SDE, SIL, and PLP.

  • SDS stands for Source Dependent Data Store. In this phase, a separate schema on the data warehouse database is maintained as a replication of the source transactional systems’ tables, deletions, as well as additional optimizations for incremental ETL. Each SDS requires its own separate schema because there can be multiple SDS each having the same object names. Typically, you see a corresponding load plan step, SDS Load Phase, in your generated load plan when you enable extraction from cloud sources, for example when extracting data from Fusion Cloud, Taleo Cloud, and so on. SDS Load Phase tasks extract data from cloud sources and stage it in SDS tables.

  • Health Check. Health Check is a preliminary ETL phase in which a diagnostic report is generated to identify problematic source data that might cause ETL failure or data loss or corruption in the data warehouse. The report is downloaded from Configuration Manager and includes any problematic data, a description of detected issues, and actions to resolve health check failures.

  • SDE stands for Source Dependent Extract. In this phase, SDE tasks extract data from the source system and SDS and stage it in staging tables. The SDE tasks are source specific.

  • SIL stands for Source Independent Load. Load tasks transform and port the data from staging tables to base fact or dimension tables. The SIL tasks are source independent.

  • PLP stands Post Load Process. PLP tasks are only executed after the dimension and fact tables are populated. A typical usage of a PLP task is to transform data from a base fact table and load it into an aggregate table. The PLP tasks are source independent.