\n\tid INTEGER NOT NULL AUTO_INCREMENT, \n\tbody TEXT, \n\ttimestamp DATETIME, \n\tdisable BOOL, \n\tauthor_id INTEGER, \n\tpost_id INTEGER, \ n\tPRIMARY KEY (id), \n\tFOREIGN KEY(author_id) REFERENCES users (id), \n\tFOREIGN KEY(post_id) REFERENCES posts (id), \n...
CONSTRAINT `FK_BC_BP_ID` FOREIGN KEY (`BLOG_COMMENTS_POST` ) REFERENCES `blog`.`blog_posts` (`BLOG_POSTS_ID` ) ON DELETE CASCADE ON UPDATE CASCADE) ENGINE = InnoDB DEFAULT CHARACTER SET = utf8 COLLATE = utf8_unicode_ci; SET SQL_MODE=@OLD_SQL_MODE; ...
CONSTRAINT pk_sendouts PRIMARY KEY (accountid, documentid, addressid), CONSTRAINT ckc_dates CHECK (NOT (enddate < fromdate)), CONSTRAINT fk_accountid FOREIGN KEY (accountid) REFERENCES accounts (accountid), CONSTRAINT fk_documentid FOREIGN KEY (documentid) REFERENCES documents (documentid), CON...
id bigint GENERATED ALWAYS AS IDENTITY PRIMARY KEY, name text NOT NULL, department bigint REFERENCES department NOT NULL ); ALTER TABLE department ADD FOREIGN KEY (leader) REFERENCES employee; In this case, we want to store departments and employees. Every department will need a leader, and ev...
MYSQL外键(Foreign Key)的使用 - - C++博客
I agree that you should only store attributes as numeric types if you plan on doing math on them, but if you are using only surrogate keys as you should be, no one should ever see the primary key. I guess the question is whether the professorID is the ID numb...
描述¶ Django generates: post_id mediumint(9) unsigned auto_increment NOT NULL REFERENCES posts_posts (slug) This doesn't work. In MySQL, only one column can have auto_increment, and that same column has to be the PRIMARY KEY. I think there should be a separate DATATYPE for ForeignKey...
It seems odd that the same field would reference two tables, which means that the same data point has to be true in two different entities. Can you fill in the blanks? Viewing 9 posts - 1 through 8 (of 8 total) You must be logged in to reply to this topic.Login to reply...
protected override void OnModelCreating(ModelBuilder modelBuilder) { modelBuilder.Entity<Blog>() .HasMany(e => e.Posts) .WithOne(e => e.Blog) .HasForeignKey("MyBlogId"); } By convention, a shadow foreign key gets its type from the principal key in the relationship. This type is made ...
I have created two tables, one called 'posts' and the other 'selected_pic'. The idea is to have a table of posts that gets stored with an ID that references the image in the 'selected_pic' table. From what i have gathered, using Foreign keys is probably the best way y do this?