Data Lake vs. Data Warehouse – Comparison Overview

Feature Data Lake Data Warehouse
Data Type Raw, unstructured, semi-structured, and structured Structured and semi-structured
Schema Schema-on-read Schema-on-write
Purpose Store large volumes of raw data for analytics, ML, and big data use Optimized for querying and reporting with curated data
Users Data engineers, scientists, ML developers Business analysts, BI users
Performance Depends on external tools; slower for complex queries High performance for structured queries
Data Quality Accepts all data, including unclean/raw data Requires clean, validated data with schema
Cost Lower storage cost (especially in cloud) Higher due to compute and optimization layers
Examples (GCP) Cloud Storage, Cloud Bigtable BigQuery, Cloud SQL
Scalability Scales easily for massive raw data volumes Scales well for structured data with some limitations
Best For Machine learning, raw data storage, streaming Business reporting, dashboards, fast queries
Data Ingestion Any data, batch and real-time Only transformed/cleaned data
Storage Format Supports formats like Parquet, Avro, JSON, CSV Optimized columnar/row formats for analysis