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What is the difference between inner join and outer join in SQL?
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 join and full outer join same?
3 Answers. Actually they are the same. LEFT OUTER JOIN is same as LEFT JOIN and RIGHT OUTER JOIN is same as RIGHT JOIN .
What is a full join?
A FULL JOIN returns all the rows from the joined tables, whether they are matched or not i.e. you can say a full join combines the functions of a LEFT JOIN and a RIGHT JOIN . Full join is a type of outer join that’s why it is also referred as full outer join.
What is faster Left join or inner join?
A LEFT JOIN is absolutely not faster than an INNER JOIN . In fact, it’s slower; by definition, an outer join ( LEFT JOIN or RIGHT JOIN ) has to do all the work of an INNER JOIN plus the extra work of null-extending the results.
When to use inner join vs outer join?
You use INNER JOIN to return all rows from both tables where there is a match. i.e. In the resulting table all the rows and columns will have values. In OUTER JOIN the resulting table may have empty columns. Outer join may be either LEFT or RIGHT .
Is inner join more efficient than join?
What is inner join in SQL?
Definition of SQL Inner Join Inner Join clause in SQL Server creates a new table (not physical) by combining rows that have matching values in two or more tables. This join is based on a logical relationship (or a common field) between the tables and is used to retrieve data that appears in both tables.
What is a full join SQL?
The SQL FULL JOIN combines the results of both left and right outer joins. The joined table will contain all records from both the tables and fill in NULLs for missing matches on either side.
What is difference between inner join and left join?
INNER JOIN: returns rows when there is a match in both tables. LEFT JOIN: returns all rows from the left table, even if there are no matches in the right table. RIGHT JOIN: returns all rows from the right table, even if there are no matches in the left table.
Why use LEFT join instead of inner join?
Generally, we use INNER JOIN when we want to select only rows that match an ON condition. We use a LEFT JOIN when we want every row from the first table, regardless of whether there is a matching row from the second table. This is similar to saying, “Return all the data from the first table no matter what.