🌱 12 Common Mistakes and Missed Optimization Opportunities in SQL

Be Careful When Dividing Integers Guard Against “division by zero” Errors Know the Difference Between UNION and UNION ALL Be Careful When Counting Nullable Columns Be Aware of Timezones Avoid Transformations on Indexed Fields Use BETWEEN Only For Inclusive Ranges Add “Faux” Predicates Inline CTE* Fetch Only What You Need! Reference Column Position in GROUP BY and ORDER BY Format Your Query