1
I have the following tables:
livroautor
id idautor idlivro
------ ------- ---------
1 1 (NULL)
2 2 2
3 3 3
4 4 4
5 5 5
6 6 (NULL)
7 7 5
8 8 2
9 9 2
10 10 (NULL)
book
id titulo resumo isbn paginas categoria
------ -------------------------- ------ ------ ------- ---------------------------
1 Any Which Way You Can (NULL) (NULL) (NULL) Comedy
2 Nitro Circus: The Movie (NULL) (NULL) (NULL) Action|Comedy|Documentary
3 Imaginary Heroes (NULL) (NULL) (NULL) Comedy|Drama
4 Nightmare in Las Cruces, A (NULL) (NULL) (NULL) Documentary
5 Boys Next Door, The (NULL) (NULL) (NULL) Crime|Drama
author
id nome sobrenome email
------ ------- ----------- --------------------------------
1 Maddy Garnsworthy [email protected]
2 Elsy Kernoghan [email protected]
3 Eduard Jehan [email protected]
4 Leone Elizabeth [email protected]
5 Maurita Ferraron [email protected]
6 Sawyer Szimoni [email protected]
7 Emmy Trudgeon [email protected]
8 Wynnie McKoy [email protected]
9 Buiron Vian [email protected]
10 Bruis Naisey [email protected]
I need to select all books that do not have registered authors, only I have no idea how to do it. I’m supposed to use JOIN
, only I don’t have much knowledge of this command.
Thank you in advance.
friend, you did not make confusion as the columns of the table Bookmaker? the column book has null fields, that’s right?
– Geilton Xavier Santos de Jesus