Is Cross join same as inner join?
CROSS JOIN is the full cartesian product of the two sides of a JOIN. INNER JOIN is a reduction of the cartesian product—we specify a predicate and get a result where the predicate matches. LEFT, RIGHT and FULL OUTER JOINs simply change the side on which unmatched rows are kept.
How do I get unique values from an inner join?
You can use CTE to get the distinct values of the second table, and then join that with the first table. You also need to get the distinct values based on LastName column. You do this with a Row_Number() partitioned by the LastName, and sorted by the FirstName.
Where is cross join used?
A cross join is used when you wish to create a combination of every row from two tables. All row combinations are included in the result; this is commonly called cross product join. A common use for a cross join is to create obtain all combinations of items, such as colors and sizes.
Can a table have more records than an inner join?
Inner Join can for sure return more records than the records of the table. Inner join returns the results based on the condition specified in the JOIN condition. If there are more rows that satisfy the condition (as seen in query 2), it will return you more results. Reference: Introduction to Join – Visual Explanation.
Which is the result of a cross join?
The result of the join can be defined as the outcome of first taking the Cartesian product (or Cross join) of all records in the tables (combining every record in table A with every record in table B) and then returning all records which satisfy the join predicate.
When to use inner join in SQL Server?
Here you will see the normal use of INNER JOIN where a query returns the results as the number of rows or fewer than the number of rows in the table. This happens because the data is unique in both of the tables.
Why does inner join return more rows than exists?
Inner join returns the results based on the condition specified in the JOIN condition. If there are more rows that satisfy the condition (as seen in query 2), it will return you more results. Reference: Introduction to Join – Visual Explanation. Well, feel free to send your questions or even solutions.