Difference between left join and left outer join in mysql

In this article we will show you, How to write MySQL Left Join with example using Command Prompt, and Workbench. What is the difference between INNER JOIN. MySQL : Which join is better between left outer join and inner join.

Main difference between LEFT and RIGHT OUTER JOIN is that in case of former, unmatched rows from left table is included in result, while in case of right outer join , unmatched rows from right side of table in query is included. The OUTER join is also called FULL OUTER as opposed to LEFT and RIGHT joins that are PARTIAL of the OUTER join.

There is no difference between RIGHT JOIN and RIGHT OUTER JOIN. LEFT JOIN and LEFT OUTER JOIN are the same. Sometimes nulls will be produced in this process as some data is shared while other data is not. They produce the same result and also the same performance.

MySQL Left Join is one of the Join Type which is used to return all the records (or rows) from Left table, and matching rows from the right table. NOTE: All the Unmatched rows from right table will be filled with NULL Values. In MySQL CROSS JOIN , INNER JOIN and JOIN are the same.

In the standar and semantically, a CROSS JOIN is an INNER JOIN without an ON clause, so you get every combination of rows between tables.

You have examples of all semantic types of join on. A left outer join (also known as a left join ) retains all of the rows of the left table, regardless of whether there is a row that matches on the right table. The SQL above will give us the result set shown below.

The INNER JOIN pertains to only elements with the join condition(s) existing in both tables joined. This really doesn’t add anything to the replies of others. Difference between Left Join and Left Outer Join. The join can either be an inner join or an outer join. An inner join returns records which have matches in both tables as opposed to an outer join which is the opposite of the inner.

The outer join therefore returns those records that do not have matches in either table. Id ORDER BY TotalAmount This will list all customers, whether they placed any order or not. Initially, it applies inner join on Table_A and Table_B to retrieve matching tuples from both the tables. Full Outer Join is the combination of both, Left Outer Join and Right Outer Join. Then it extends those tuples of Table_A with NULL that do not have a matching tuple in Table_B.

The main difference between LEFT OUTER JOIN and RIGHT OUTER JOIN is: LEFT OUTER JOIN returns all records from the LEFT table irrespective of whether there are any matching rows in the RIGHT table. Where as RIGHT OUTER JOIN returns all records from the RIGHT table irrespective of whether there are any matching rows in the LEFT table. Outer joins are specified with one of the following sets of keywords when they are specified in the FROM clause: 2.

In case of no match with right side table it will return NULL value. Left Join” and “Left Outer Join” are used interchangeably because records which are returned will be the same with either of these. I thought there was different types of Left Joins : Left (Inner) Join and Left Outer Join. There’s a Venn diagram that clearly shows the difference , but I’m reading online that there’s actually no difference between the two? The right outer join does not add any functionality that the left outer join didn’t already have, and vice versa.

The only thing is that an extra keyword outer ! Basically Outer join is of three types : 1. The rows for which there is no matching row on right side, result contains NULL in the right side. Left outer join returns all rows of table on left side of join. When you begin building queries using OUTER JOIN , the SQL Standard considers the first table you name as the one on the left , and the second table as the one on the right.

The same is true of a RIGHT JOIN and a RIGHT OUTER JOIN.