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In this window, a warning message leaps to our eyes. In the generated actual execution plan, we will see a Nested loops operator and when we hover over the mouse on this operator, the detail pop-up window will appear. For the following query, we will analyze the execution plan with ApexSQL Plan. We try to say that these queries have a high potential to consume more resources and can cause performance issues. The SQL queries which contain the CROSS JOIN keyword can be very costly. SQL CROSS JOIN and Performance Considerations The syntax of the CROSS JOIN in SQL will look like the below syntax: Suppose that, A is a set and elements are Syntax The Cartesian Product is a multiplication operation in the set theory that generates all ordered pairs of the given sets. In the following tip, we will briefly explain the Cartesian product

The main idea of the CROSS JOIN is that it returns the Cartesian product of the joined tables.

“Please don’t worry, even if you feel a bit hungry now, you can eat whatever you want after reading our article.” The SQL CROSS JOIN works similarly to this mechanism, as it creates all paired combinations of the rows of the tables that will be joined. The following image illustrates all menu combinations that can be generated by our brain. Our brain will receive this signal and begin to generate all meal and drink combinations. Shortly, we will look at the menu and we will start thinking of which meal and drink combination could be more tastier. Suppose that we are sitting in a coffee shop and we decide to order breakfast. This join type is also known as cartesian join. The CROSS JOIN is used to generate a paired combination of each row of the first table with each row of the second table. In this article, we will learn the SQL CROSS JOIN concept and support our learnings with straightforward examples, which are explained with illustrations.