Once again a short reminder how to aggregate SQL statement execution results as a single XML CLOB in Oracle.

Assume there is an Oracle table containing user data:

create table t_user(
	user_id		number(15) not null,	
	user_name	varchar2(100) not null,		
	role		varchar2(100) not null,			
	email		varchar2(100)	
)
/

Now aggregating all the user entries as single XML CLOB can be done using following statement:

select xmlelement("users",
                  xmlagg(xmlelement("user",
                                    xmlattributes(    t.user_id as "id",
                                                      t.user_name as "name",
                                                      t.role,
                                                      t.email
                                    )
            ))
        ).getclobval() xml
from t_user t

This will result in a CLOB that looks like this:

<users>
	<user id="1" name="foo" role="USER" email="[email protected]"></user>
	<user id="2" name="bar" role="ADMIN" email="[email protected]"></user>
	...
	<user id="999" name="xyz" role="USER" email="[email protected]"></user>
</users>