DeWu Technology

Jan 19, 2026 · Big Data

How to Speed Up Full‑Scale Data Comparison for Massive Migration Projects

This article details the challenges of comparing billions of rows during large‑scale data migrations, presents a multi‑step solution using union‑all grouping, hash‑based aggregation, and intelligent primary‑key detection, and explains platform features, performance optimizations, and future enhancements that reduced comparison time by up to 70%.