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What are left outer joins?
A left outer join is a method of combining tables. The result includes unmatched rows from only the table that is specified before the LEFT OUTER JOIN clause. If you are joining two tables and want the result set to include unmatched rows from only one table, use a LEFT OUTER JOIN clause or a RIGHT OUTER JOIN clause.
What is right outer join example?
A right outer join is a method of combining tables. The result includes unmatched rows from only the table that is specified after the RIGHT OUTER JOIN clause. If you are joining two tables and want the result set to include unmatched rows from only one table, use a LEFT OUTER JOIN clause or a RIGHT OUTER JOIN clause.
What is left outer join in Oracle with example?
Another type of join is called an Oracle LEFT OUTER JOIN. This type of join returns all rows from the LEFT-hand table specified in the ON condition and only those rows from the other table where the joined fields are equal (join condition is met).
What is the difference between left 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 the difference between left and right outer join?
The key difference between a left outer join, and a right outer join is that in a left outer join it’s the table in the FROM clause whose all rows are returned. Whereas, in a right outer join we are returning all rows from the table specified in the join clause.
What is the difference between full outer join and outer join?
Full Outer Join returns all the rows from both the table. When no matching rows exist for the row in the left table, the columns of the right table are null padded. Full outer join is the union of left outer join and right outer join.
What is difference between left join and left outer join?
What is the function of a full outer join?
The FULL OUTER JOIN keyword returns all records when there is a match in left (table1) or right (table2) table records.
What does LEFT OUTER JOIN do in SQL?
It returns all the rows from a left table and the matching rows from the right table. This means that the left join returns all the values from a left table, plus matched values from a right table or NULL in the case of no matching join predicate. In some SQL databased LEFT OUTER JOIN is also called as LEFT JOIN.
Is the left join the same as the inner join?
JOIN is same as INNER JOIN. This query will show the names and age of students enrolled in different courses. LEFT JOIN: This join returns all the rows of the table on the left side of the join and matching rows for the table on the right side of join.
Is there a Venn diagram for SQL LEFT OUTER JOIN?
It is because EmpID 11 is not available in the Employee table. As a summary, we can represent SQL Left Outer Join using the following Venn diagram. We get the highlighted area in the output of SQL Left Outer Join. In SQL Right Outer Join, we get the following rows in our output.
What happens if there is no match in LEFT OUTER JOIN?
The result is NULL from the right side, if there is no match. Note: In some databases LEFT JOIN is called LEFT OUTER JOIN. In this tutorial we will use the well-known Northwind sample database. The following SQL statement will select all customers, and any orders they might have: