Please tell me why error is coming in my sql code

Question

create table stu (id int primary key, name varchar(50), age int not null, subject varchar(50));
insert into stu values(1, "Meenakshi", 45, "Biology");
insert into stu values(2, "Roma", 32, "English");
insert into stu values(3, "Katherine", 26, "GK");
insert into stu values(5, "Shravya", 39, "Maths");
insert into stu values(6, "Jyoti", 41, "Geography");
insert into stu values(7, "Jyoti", 51, "History");
delete from stu where age=51;
select * from stu

I am getting this error--

0 27 23:46:19 delete from stu where age=51 Error Code: 1175. You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column.
To disable safe mode, toggle the option in Preferences -> SQL Editor and reconnect. 0.000 sec

Please help me rectify the error.

Answer 1

as I see: in sql you need ";" at the end of the statements;

Answer 2

I don't think the code has error, only the engine setting prevent the code to run.

As the Error Code says:
You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column.
To disable safe mode, toggle the option in Preferences...

Imagine you have the 8 entry like this:
insert into stu values(8, "Wong", 51, "Japanese");

If you run "delete from stu where age=51", which record should be deleted? 7, 8, or both?

The proper way would be:
delete from stu where id=7;
Using the KEY (id) as suggested.

If you turn-off safe mode as the error code suggested and run your original code with the 8 entry, both id 7 & 8 will get deleted, and this may not be the result you wanted.