DBMS 似乎在交易中提交（新手问题）

Question

I am using the batabase that is shown in the following relational diagram:

And using the following SQL script, I am trying to add a new book along with its new author as well as new genre (no ratings at this points) (I am using MySQL like most students):

use booksdb;
start transaction;
insert into genre values ('Educational');
insert into books values ('123456789', 'Databases Illuminated',null, '1990,01,01' );
insert into book_genre values('123456789','Educational');
insert into authors(firstName, familyName) values ('Catherine','Ricardo');
insert into writes values('123456789',LAST_INSERT_ID());
COMMIT;

And I am having two problems: The first is that the DBMS is telling me that I am trying to add a tuple that contains a reference that does not exist in the referenced table (Error Code: 1452. Cannot add or update a child row: a foreign key constraint fails). And my first question is, is not the whole poind of using transaction is so that no constrains will be enforced/checked untill the transaction is complete? (In which case everything should be in its place with no "empty references"). The only way I am able to add everything is by doing it one line each time I press Excute button. The second qusetion is: Should I add primary keys first or forig ones? The "obvious" answer I thought is that I needed to add PK's first, but even if I arrange all the lines in the scripts so that PK's are always added first, I am still getting Error Code: 1452, the only way I could add everything is to feed the script lines to the DBMS one line at a time. There is obviously something fundamentally wrong in my understanding of how this should work, I tried to look it up many times here and on Google but could not find the answer.

Answer 1

Alrghit, I found what I was doing wrone. In the relational diagram I made the relation between books and book_genre one to many where the many side is books, and it should have been the other way around. I tried to flip it and so far I do not have any problems.