How to send USERPRINCIPALNAME to dynamic query to return results based on logged in user

Hi,

I have a requriement to show data based logged in user. The logged in user (USERPRINCIPALNAME) need to be passed to query as  a parameter user_id to the backend direct query. Data is huge cannot do import mode.

For example --

select sec_lev_grant from table  where upper(user_id) = upper('[email protected]')

Thanks in advance