Best Practices

Query Optimization

• Use proper indexes on date columns used for filtering

• Avoid SELECT * queries; specify required columns

• Use LIMIT for testing phases

• Consider query execution time and add pagination for large datasets

Error Handling

• Always include try-catch blocks around database operations

• Log meaningful error messages with context

• Implement retry logic for transient failures

• Ensure database connections are properly closed

Security

• Never hardcode credentials in scripts

• Use environment variables or AWS Parameter Store

• Implement least-privilege access for database users

• Use VPN or private networks for database connections

Performance

• Process data in batches for large datasets

• Use connection pooling for multiple queries

• Monitor memory usage with large DataFrames

• Consider parallel processing for independent queries

Monitoring

• Implement comprehensive logging at INFO level

• Track record counts for data validation

• Monitor S3 upload success/failure rates

• Set up alerts for pipeline failures