Wednesday, 17 January 2018

ETL - Designing

ETL design is one of key processes of a DWH project. Improperly designed ETL systems lead to considerable complexity and significant operational problems in later phase of the project which costs extra time and resources due to issues and required rework.

To design a good ETL system, ETL designers should follow basic steps in respective phases of the project as below -

Requirement Gathering
Data Analysis and Profiling(5D)
            Data Integrity
            Data Volume
            Data Distribution
            Data Availability
            Data Velocity
            Logical Data Modelling
            Source to Target Mapping
Database and ETL Design
            ETL design guidelines
                        Extraction
                        Transformation
                        Load
            ETL best practices
            ETL strategies for known problems
ETL Development
            ETL best practices
            Development Tracker, Estimation and Project Plan
ETL Testing
            Testing setup activities
            Stats collection
            Performance tuning
Implementation
            Implementation Plan
            Backout Plan
            ETL support documentation