irst and most important: very detailed instruction by the author and good to check if you need to explore the concepts!
https://colab.research.google.com/drive/1FiAHNFenM8RyptyTPtDTfqPCi5W6KX_V?usp=sharing#scrollTo=ew7-fr5EuyOu
The Data Lakehouse architecture combines the best features of data lakes and data warehouses through intelligent metadata management:
1. Schema Management Approaches
a) Write-time Schema Definition:
- Pre-defined schema like traditional warehouses
- Strict data validation during ingestion
- Example:
table.create("events", schema=("id STRING", "timestamp LONG"))
b) Read-time Schema Inference:
- Dynamic schema detection like data lakes
- Flexible data ingestion
- Example:
table.create("events", schema="infer")
c) Hybrid Mode (Most Common):
- Combines both approaches
- Allows schema evolution
2. Metadata Layer Operations
Data Flow:
Raw Data → Schema Check/Inference → Metadata Update → Storage
↓
Metadata Catalog Update
↓
Statistics Generation
3. Schema Evolution Mechanism
// Initial Data Structure
{
"user_id": "123",
"action": "login",
"timestamp": "2024-02-16T10:00:00"
}
// Evolution with New Fields
{
"user_id": "124",
"action": "login",
"timestamp": "2024-02-16T10:05:00",
"device": "mobile", // New field
"location": "CN" // New field
}
4. Core Metadata Management Features
Raw Logs → Cleansed Data → Aggregated Stats → Analytics
↓ ↓ ↓ ↓
Metadata1 Metadata2 Metadata3 Metadata4