SQLAlchemy

Fixing Silently Missing Rows After SQLAlchemy Bulk Insert with on_conflict_do_nothing

Bulk inserts combined with PostgreSQL's ON CONFLICT DO NOTHING can dramatically improve performance and simplify deduplication. However, many developers are surprised when rows silently disappear during large imports. Learn why missing rows occur, how SQLAlchemy handles conflicts, and how to safely

Jun 28, 2026 5m read 👁 13

Fixing Silently Skipped Rows in SQLAlchemy bulk_insert_mappings Calls

Learn why SQLAlchemy's bulk_insert_mappings() may silently skip rows during bulk operations and discover practical techniques to identify, troubleshoot, and fix missing records. This guide covers validation, constraints, transaction handling, logging, and best practices..

Jun 14, 2026 4m read 👁 25