Why ORDER BY is Unpredictable in SQL

In SQL, the ORDER BY clause is used to sort the result set of a query based column(s). However, the sorting behavior cannot be guaranteed to be consistent across different executions of the same query. In this article, we are gonna explore the reasons that might cause these inconsistencies and how to ensure that your queries return predictable results.

Problem Introduction

The Default State: The "Unordered" Nature of SQL

When ORDER BY Seems to Fail: Common Pitfalls

Case Study: The Danger of Non-Deterministic Sorting

Database Specifics: PostgreSQL vs. MySQL vs. SQL Server

Best Practices for Deterministic Results

Conclusion: Sorting as a Contract