First recognized for XML Path

Today, the company's upgrade exam (I am familiar with soy sauce), the result of the first question turned off, probably like this:

A student table with stuid, sname, and holobby columns respectively. stuid indicates the student ID, sname indicates the Student name, And Hoby indicates the interests of students.

The requirement is to query the student table and display the result set of all students' hobbies.

I didn't figure it out for a long time, and then I asked my colleague, he said he used the for XML Path to figure it out.

Select B. sname, left (stulist, Len (stulist)-1) as holobby from (select sname, (select holobby + ', 'From student where sname =. sname for XML Path ('') as stulist from student a group by sname) B

In fact, for XML Path is to display the query result set in XML format.