Data Cleaning & Join Automation

Data Profiling & Validation: Analyzed column distributions and flagged anomalies (nulls, outliers) using conditional checks and descriptive aggregates.

Cleaning & Standardization: Removed duplicates, imputed or filtered out NULLs based on business rules, and standardized text formats (trimming, case normalization) to ensure consistency across tables.

Type Casting & Transformation: Converted columns to appropriate data types and applied value transformations—such as date formatting and numeric rounding—to align with reporting requirements.

Complex Joins & Aggregations: Consolidated cleaned tables through INNER and LEFT JOIN operations, linking transactional, customer, and product data. Aggregated sales metrics by customer segment and time period to produce a unified analytics-ready table.

Indexing & Performance Optimization: Created indexes on join keys and applied query hints to improve execution speed on large datasets, reducing runtime by over 40%.