Data Engineering Roadmap
- Sairam Penjarla
- Jun 7, 2024
- 2 min read
Extract
Purpose: To gather data from different sources.
Sources:
Databases (SQL, NoSQL)
Files (CSV, JSON, XML)
APIs and Web Services
Third-party systems (CRM, ERP)
Tools and Techniques:
SQL Queries
Web Scraping
Data Extraction Tools (e.g., Apache Nifi, Talend)
Transform
Purpose: To convert the extracted data into a format suitable for analysis or loading.
Common Transformations:
Data Cleaning: Removing duplicates, handling missing values, correcting errors.
Data Integration: Combining data from different sources.
Data Aggregation: Summarizing data (e.g., computing averages, sums).
Data Enrichment: Adding additional information to data.
Normalization and Denormalization: Structuring data to reduce redundancy or to flatten data structures.
Data Type Conversion: Changing data types (e.g., string to date).
Tools and Techniques:
Scripting Languages (Python, R)
ETL Tools (e.g., Apache Spark, Talend, Informatica)
SQL Transformations
Load
Purpose: To load the transformed data into a target database or data warehouse.
Targets:
Data Warehouses (e.g., Amazon Redshift, Google BigQuery)
Databases (e.g., MySQL, PostgreSQL)
Data Lakes (e.g., Hadoop, Amazon S3)
Loading Techniques:
Full Load: Loading all the data at once.
Incremental Load: Loading only the new or updated data since the last load.
Batch Processing: Loading data in batches at scheduled intervals.
Real-Time Processing: Continuously loading data in real-time.
Tools and Techniques:
ETL Tools (e.g., Apache Nifi, Talend, Informatica)
Data Load Scripts (SQL, Python)
Streaming Platforms (e.g., Apache Kafka)
Key Concepts and Best Practices
Data Quality: Ensuring the data is accurate, complete, and reliable throughout the ETL process.
Scalability: Designing ETL processes that can handle increasing volumes of data efficiently.
Error Handling and Logging: Implementing mechanisms to capture errors and log activities for monitoring and debugging.
Automation and Scheduling: Using tools to automate ETL workflows and schedule them to run at specific times.
Documentation: Keeping thorough documentation of ETL processes, data sources, transformation logic, and data mappings.
Common ETL Tools
Informatica PowerCenter: A widely used enterprise data integration tool.
Talend: An open-source ETL tool with a rich set of features for data integration.
Apache Nifi: A data integration tool that supports data flow automation.
Apache Spark: A powerful data processing engine that can be used for ETL tasks.
Pentaho Data Integration (PDI): An open-source ETL tool also known as Kettle.
Microsoft SQL Server Integration Services (SSIS): A data integration tool provided by Microsoft.
Data Mapping and Conversion
Mapping changes between source and target systems (Eg: column name differences).
Incremental Loading
Change Data Capture (CDC)
Error Handling
Parallel Processing
Job Scheduling
Dependency Management
Data Quality Checks
Metadata Management
Data Modeling
Entity-Relationship Diagrams (ERD)
Star Schema
Snowflake Schema
Normalization (1NF, 2NF, 3NF)
Surrogate Keys
Composite Keys
NoSQL Data Modeling
Table Naming Conventions
Column Naming Conventions
Database Naming Conventions
Data Validation Rules
Logging and Auditing
Staging Environment
Batch Processing