create table t1(id int primary key, val int);

insert into t1 values(1,1),(2,2),(3,3);

set session sql_safe_updates=ON;

delete from t1;

-- ERROR 1175 (HY000): You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column

delete from t1 where 1=1;

-- ERROR 1175 (HY000): You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column

delete from t1 where id = id;

-- ERROR 1175 (HY000): You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column

delete from t1 where id is not null;

ERROR 1175 (HY000): You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column

delete from t1 where id > 0;

-- Query OK, 3 rows affected (0.001 sec)