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Can we use inner join without on clause?
When using join or inner join , the on condition is optional. The effect is a cross join . Similarly, you can use an on clause with cross join , which also differs from standard SQL. A cross join creates a Cartesian product — that is, every possible combination of 1 row from the first table and 1 row from the second.
Can we have NULL values in inner join?
A join that displays only the rows that have a match in both joined tables. Columns containing NULL do not match any values when you are creating an inner join and are therefore excluded from the result set. Null values do not match other null values.
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.
What is the purpose of the inner join clause?
The INNER JOIN clause matches rows in one table with rows in other tables and allows you to query rows that contain columns from both tables. For example, you can join tables that have key relationships like the Courselines and Courses tables.
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 INNER JOIN statement?
An INNER JOIN is such type of join that returns all rows from both the participating tables where the key record of one table is equal to the key records of another table. This type of join required a comparison operator to match rows from the participating tables based on a common field or column of both the tables.