SQL连接表需要调整查询

Question

查询工作正常，但我想补充说，该类型应该只是戏剧

Select writer.writer_name, book.book_genre,publisher.publisher_name 
from writer,book,publisher where  writer.writer_id=book.writer_id 
and publisher.publisher_id=book.publisher_id;

Answer 1

a_horse_with_no_name表示使用它：

Select 
  writer.writer_name, 
  book.book_genre,
  publisher.publisher_name 
from writer
join  book on writer.writer_id = book.writer_id
join  publisher on book.publisher_id = publisher.publisher_id

where book.book_genre = 'drama'

使用显式连接而不是滥用where子句来连接表。调整＆＃39;＆＃39;＆＃39;＆＃39;大约'drama'以适合你的数据库。