Sql, Sql Optimization, Database Optimization, Data Processing, Data Management.
NULL where there’s no match. Use INNER JOIN, LEFT JOIN, RIGHT JOIN or FULL OUTER JOIN based on the relationship between tables. INNER JOINs are generally faster than OUTER JOINs. SELECT * FROM table1 INNER JOIN table2 ON table1.id = table2.id; Avoid Nested Queries: Think of a library where you have