#sqltips — Public Fediverse posts

SQL Anti-Patterns You Should Avoid

https://datamethods.substack.com/p/sql-anti-patterns-you-should-avoid

#HackerNews #SQL #AntiPatterns #DataManagement #BestPractices #SoftwareDevelopment #DatabaseDesign #SQLTips

SQL Anti-Patterns You Should Avoid

https://datamethods.substack.com/p/sql-anti-patterns-you-should-avoid

#HackerNews #SQL #AntiPatterns #DataManagement #BestPractices #SoftwareDevelopment #DatabaseDesign #SQLTips

SQL Anti-Patterns You Should Avoid

https://datamethods.substack.com/p/sql-anti-patterns-you-should-avoid

#HackerNews #SQL #AntiPatterns #DataManagement #BestPractices #SoftwareDevelopment #DatabaseDesign #SQLTips

SQL Anti-Patterns You Should Avoid

https://datamethods.substack.com/p/sql-anti-patterns-you-should-avoid

#HackerNews #SQL #AntiPatterns #DataManagement #BestPractices #SoftwareDevelopment #DatabaseDesign #SQLTips

SQL queries don't start with SELECT (2019)

https://jvns.ca/blog/2019/10/03/sql-queries-don-t-start-with-select/

#HackerNews #SQLQueries #SQLTips #DatabaseProgramming #TechBlog #DataAnalysis

Check out these 2 queries:

Query 1:

SELECT ...
FROM t1
JOIN t2 ON t1.id IN (t2.id1, t2.id2);

Query 2:

SELECT ...
FROM t1
JOIN t2 ON t1.id = t2.id1
UNION
SELECT ...
FROM t1
JOIN t2 ON t1.id = t2.id2;

They both return the same data but since most database engines struggle with OR joins, the latter will outperform the former by at least an order of magnitude.

#SQLTips #DatabaseOptimization #PerformanceTuning