What is an outer join?

An outer join is used to return results by combining rows from two or more tables. But unlike an inner join, the outer join will return every row from one specified table, even if the join condition fails.

What is difference between inner and outer join?

The major difference between inner and outer joins is that inner joins result in the intersection of two tables, whereas outer joins result in the union of two tables.

IS LEFT join inner or outer?

LEFT JOIN and RIGHT JOIN are types of OUTER JOIN s. INNER JOIN is the default — rows from both tables must match the join condition.

What is left outer join and right outer join?

There are two kinds of OUTER joins in SQL, LEFT OUTER join and RIGHT OUTER join. LEFT outer join includes unmatched rows from the table written on the left of the join predicate. On the other hand, RIGHT OUTER join, along with all matching rows, includes unmatched rows from the right side of the table.

What is outer join example?

The FULL OUTER JOIN (aka OUTER JOIN ) is used to return all of the records that have values in either the left or right table. For example, a full outer join of a table of customers and a table of orders might return all customers, including those without any orders, as well as all of the orders.

What is outer join and why it is used explain its type with example?

Outer Join is a join that can be used to return the records in both the tables whether it has matching records in both the tables or not. The outer join can be further divided into three types: Left-Outer Join. Right-Outer Join.

What is difference between union and join?

UNION in SQL is used to combine the result-set of two or more SELECT statements. The data combined using UNION statement is into results into new distinct rows. JOIN combines data from many tables based on a matched condition between them. It combines data into new columns.

What is the difference between left join and right join?

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.

Is there a difference between left join and left outer join?

There really is no difference between a LEFT JOIN and a LEFT OUTER JOIN. Both versions of the syntax will produce the exact same result in PL/SQL. Some people do recommend including outer in a LEFT JOIN clause so it’s clear that you’re creating an outer join, but that’s entirely optional.

What is difference between left outer join and outer join?

What is difference between full outer join and cross join?

For SQL Server, CROSS JOIN and FULL OUTER JOIN are different. CROSS JOIN is simply Cartesian Product of two tables, irrespective of any filter criteria or any condition. FULL OUTER JOIN gives unique result set of LEFT OUTER JOIN and RIGHT OUTER JOIN of two tables.

Where do we use outer join?

Outer joins are used to match rows from two tables. Even if there is no match rows are included. Rows from one of the tables are always included, for the other, when there are no matches, NULL values are included.

When to use an outer join?

An outer join is used to return results by combining rows from two or more tables. But unlike an inner join, the outer join will return every row from one specified table, even if the join condition fails.

What is RIGHT OUTER JOIN?

A RIGHT OUTER JOIN is one of the JOIN operations that allow you to specify a JOIN clause. It preserves the unmatched rows from the second (right) table, joining them with a NULL in the shape of the first (left) table. A LEFT OUTER JOIN B is equivalent to B RIGHT OUTER JOIN A, with the columns in a different order.

What is LEFT OUTER JOIN in MySQL?

MySQL Left Join. MySQL Left Join or Left outer join is used to return all the records (or rows) from Left table, and matching rows from the right table.

What is the difference between “inner join” and “outer join”?

Key Differences Between Inner Join and Outer Join The basic difference between the Inner Join and Outer Join is that inner join compares and combine only the matching tuples from both the tables. The database size of the resultant obtained from the Inner Join is smaller that Outer Join. There are three types of the Outer Join Left Outer Join, Righ Outer Join, and Full Outer Join.