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In SQL Server, the cartesian product is really a cross-join which returns all the rows in all the tables listed in a query: each row in the first table is paired with all the rows in the second table. This happens when there is no relationship defined between the two tables.

## Why we use CARTESIAN JOIN in SQL?

In SQL, the CROSS JOIN is used to combine each row of the first table with each row of the second table. It is also known as the Cartesian join since it returns the Cartesian product of the sets of rows from the joined tables.

## What is difference between CARTESIAN JOIN and cross join?

Both the joins give same result. Cross-join is SQL 99 join and Cartesian product is Oracle Proprietary join. A cross-join that does not have a ‘where’ clause gives the Cartesian product. Cartesian product result-set contains the number of rows in the first table, multiplied by the number of rows in second table.

## Is CARTESIAN 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.

## What is Cartesian and self join?

To avoid errors and confusion, t1 and t2 are used along T for comparing two rows in the same table. Inner join or Left join is used for self join to avoid errors. 2. … It is similar to the cartesian product that joins all the rows.

## What is the difference between Cartesian product and joins?

Cross-join is SQL 99 join and Cartesian product is Oracle Proprietary join. A cross-join that does not have a ‘where’ clause gives the Cartesian product. Cartesian product result-set contains the number of rows in the first table, multiplied by the number of rows in second table.

## What is Cartesian product in SQL Server?

In SQL Server, the cartesian product is really a cross-join which returns all the rows in all the tables listed in a query: each row in the first table is paired with all the rows in the second table. This happens when there is no relationship defined between the two tables. An Example.

## Which join is equal to Cartesian product?

A CROSS JOIN is a JOIN operation that produces the Cartesian product of two tables. Unlike other JOIN operators, it does not let you specify a join clause.

## What is the difference between Cartesian product and full outer join?

A cross join produces a cartesian product between the two tables, returning all possible combinations of all rows. It has no on clause because you’re just joining everything to everything. A full outer join is a combination of a left outer and right outer join.

## Can you join two tables without using the keyword join?

Yes, it is possible to join two tables without using the join keyword. … Cross join is also known as cartesian join. If we specify the WHERE condition to the join which we just have seen, we can also convert the same cross join to inner join as well.

## Which join yields more records?

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.

## Which SQL join is used for joining the table itself?

A self join is a regular join, but the table is joined with itself.

## When to use outer join and inner 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.

## What does <> operator mean in SQL?

Compares two expressions (a comparison operator). When you compare nonnull expressions, the result is TRUE if the left operand is not equal to the right operand; otherwise, the result is FALSE.

## Why is it called Cartesian product?

The Cartesian product is named after René Descartes, whose formulation of analytic geometry gave rise to the concept, which is further generalized in terms of direct product.

## What is left outer join in SQL?

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.