SQLZOO, Cannot DELETE because of reference.

Cannot DELETE because of reference.

Postgres
If a foreign key is set up between two tables it may be that you cannot delete a record. In this case the table t_staff references the table t_dept - you cannot delete the department 'co' if a member of staff belongs to that department.	Execute set up code DROP TABLE t_staff; DROP TABLE t_dept; CREATE TABLE t_dept(id CHAR(2), fname VARCHAR(20),PRIMARY KEY(id)); CREATE TABLE t_staff(name VARCHAR(20), dept CHAR(2), PRIMARY KEY(name), FOREIGN KEY(dept) REFERENCES t_dept(id)); INSERT INTO t_dept VALUES ('co','School of Computing'); INSERT INTO t_staff VALUES ('Andrew','co') DELETE FROM t_dept WHERE id='co'
Specific to Postgres
none

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