ZetaSQL supports the following security functions.
SESSION_USER()
Description
For first-party users, returns the email address of the user that is running the query. For third-party users, returns the principal identifier of the user that is running the query. For more information about identities, see Principals.
Return Data Type
STRING
Example
SELECT SESSION_USER() as user;
+----------------------+
| user |
+----------------------+
| jdoe@example.com |
+----------------------+