# Merge Policy

> Source: https://sukruyusufkaya.com/en/glossary/merge-policy
> Updated: 2026-05-13T21:01:05.804Z
> Type: glossary
> Category: veri-muhendisligi-ve-ai-altyapisi
**TLDR:** A loading logic that defines which record should be preserved under which rule when incoming and existing records conflict.

<p>A merge policy determines how data conflicts are resolved during ETL and ELT processing. Rules such as latest update wins, most trusted source wins, or field-level merging are typical parts of this policy. In multi-source data integration, incorrectly designed merge logic can create silent data corruption. For that reason, merge policy is a critical bridge between data quality and business rules.</p>