How Grant Create Foreign Key on another schema?

I have two oracle users : User1 and User2.

• User1 has a table Users_
• User2 has a table TestTable

I'm trying to create a foreign key constraint between the two tables as follows:

ALTER TABLE "User2"."TESTTABLE" ADD CONSTRAINT "TESTTABLE_CREATEDBY"
FOREIGN KEY (CREATEDBY) REFERENCES "User1"."USERS_" (ID) ENABLE

User2 has the privilege to select on User1 table Users_ (Grant select to user2 on Users_).

When running the alter table statement I have an error of insufficient privileges.

How can I solve that?

To create a foreign key against a table in another schema we need to have the REFERENCES privilege on that table. This is a separate privilege because it imposes a burden on the table's owner: they can't delete records from their table if you're referencing them. Find out more