SQL Server CROSS APPLY and OUTER APPLY Helpful Examples

Microsoft introduced the APPLY operator in SQL Server 2005. Similar to a JOIN, it allows correlation between two table expressions. The key difference between the JOIN and APPLY operators is when you have a table-valued expression on the right side and want to evaluate it for each row from the left table expression. Since they produce similar results, when do you choose an APPLY versus a JOIN?

Unpivoting Multiple Sets of Columns in SQL Server using CROSS APPLY

Learn how to unpivot data or sets of data with SQL Server queries using CROSS APPLY.

Even More OUTER APPLY

More OUTER APPLY

Function and Queries to Convert Hierarchical Adjacency to Nested Json Arrays

This script converts hierarchical adjacency into nested json rows which contain the recursive "downlines" of each node.  The table-valued function treats each row in the original adjacency as the root node in a recursive common table expression. 

Function and Queries to Convert Hierarchical Adjacency to Nested Json Arrays

This script converts hierarchical adjacency into nested json rows which contain the recursive "downlines" of each node.  The table-valued function treats each row in the original adjacency as the root node in a recursive common table expression. 

Cross Apply

APPLY - 2

Understanding and Using APPLY (Part 2)

The second of a series by Paul White examining the APPLY operator. In this section learn how this operator compares with joins and about both the cross and outer options.

Understanding and Using APPLY (Part 1)

The first of a two-part series of articles examining the APPLY operator. Learn the basics of how this operator works and how it can help you solve some tricky problems.