Dynamic attribute in Endpoint SQL for username/endpoint

[aro]

In one endpoint I have a Dynamic Attribute of type "Single Select From SQL Query".

How can I access these automatically created and calculated fields "Security System", "Endpoint", "Account Name" and "Username" from the ARS Request Form via SQL?

I have tried different variants without success like:

select count(*) from accounts where name like CONCAT(${username},'%')

What is the right syntax?

We use Saviynt v5.5SP3

[rushikeshvartak]

select username as id from users where userkey= ${requestee.userkey} & There is no variable available for endpoint