Why is left join better than right join?
The main difference between these joins is the inclusion of non-matched rows. The LEFT JOIN includes all records from the left side and matched rows from the right table, whereas RIGHT JOIN returns all rows from the right side and unmatched rows from the left table.You'll use INNER JOIN when you want to return only records having pair on both sides, and you'll use LEFT JOIN when you need all records from the “left” table, no matter if they have pair in the “right” table or not.Common use cases for LEFT JOIN include: Displaying all items: When you want to display all items from the left table, even if there are no corresponding items in the right table. Handling missing data: When you need to handle situations where data might be missing or incomplete in one of the tables.

Why would anyone use a left join : LEFT JOIN Usage

This type of JOIN is used when you want to show all data from the left table and only the matching ones from the right. In a way, you're filtering data from the right table.

Is left join more efficient

There is not a "better" or a "worse" join type. They have different meaning and they must be used depending on it. In your case, you probably do not have employees with no work_log (no rows in that table), so LEFT JOIN and JOIN will be equivalent in results.

Which join is most efficient : Remember that both of these types of joins can improve database performance, but the inner one will perform better when the number of tuples is large, and the database is designed to support them. If you have a two-tier architecture or you have linked database features, the two-table join will work better for you.

SQL right join use cases​

But why not Simply because right joins are a little less intuitive than a left join. When you're data modeling, you're usually focused on one database object, and adding the supplementary data or tables you need to give you a final dataset.

You can observe the lack of performance because SQL inner join is slower. Outer joins, especially left outer joins, are faster and better performance in most cases. The satisfaction of the inner join condition is mandatory. There are no conditions that we have to meet in the outer join query necessarily.

Which join is fastest

In case there are a large number of rows in the tables and there is an index to use, INNER JOIN is generally faster than OUTER JOIN."In practice, explicit right outer joins are rarely used, since they can always be replaced with left outer joins and provide no additional functionality."They both have similar performance. The only thing that it differ is that which record you want to get.

Which join type you use depends on whether you want to include unmatched rows in your results:

  • If you need unmatched rows in the primary table, use a left outer join.
  • If you don't need unmatched rows, use an inner join.

Which is faster subquery or left join : Generally speaking, joins are faster than subqueries, because they can use indexes and other optimization techniques. Subqueries, on the other hand, may require more processing and memory, especially if they return large or complex results.

Which join is the best join : If you need unmatched rows in the primary table, use a left outer join. If you don't need unmatched rows, use an inner join.