Updating multiple rows with SQL and avoiding collisions

"When trying to update position values in SQL, a simple update can lead to unique constraint violations in databases like SQLite and PostgreSQL."

"When reordering items in a table with unique position values, instead of directly updating, consider temporarily negating values for significant changes."

Updating multiple rows in SQL to maintain uniqueness can lead to unique constraint violations, especially with contiguous position values in a list. A standard update could cause violations in databases like SQLite and PostgreSQL, where simultaneous updates may conflict. A more effective approach involves leveraging a transaction to temporarily negate position values, allowing for safe updating. Follow these steps: begin a transaction, temporarily negate values, decrement appropriately, and then revert the negation before committing the transaction, ensuring uniqueness without creating temporary tables.

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