What this query does to create comma delimited list SQL Server?

Question

I\'ve written this query with the help of google to create a delimited list from a table but I didn\'t understand anything from this query.

Can anyone explain me wha

Answer 1

Take it apart step by step - from the inside out.

Step 1:

Run the innermost query and see what it produces:

SELECT E2.ename AS 'data()' 
FROM emp AS e2 
WHERE e2.DEPTNO = 10
FOR XML PATH('')

You should get an output something like:

CLARK KING MILLER

Step 2:

The REPLACE just replaces spaces with , - thus turning your output into

CLARK, KING, MILLER

Step 3:

The outer query gets the deptno value - plus the results from the inner query - and produces your final result.