How to define entity relationships in TypeORM?

TypeORM defines entity relationships using the following decorators:

1. @OneToOne(): One-to-one relationship

   • Use @JoinColumn() to specify the foreign key column
   • Example: User and UserProfile

2. @OneToMany(): One-to-many relationship

   • Defined on the "one" side, pointing to the "many" side
   • Example: Author and Articles

3. @ManyToOne(): Many-to-one relationship

   • Defined on the "many" side, pointing to the "one" side
   • Example: Article and Author

4. @ManyToMany(): Many-to-many relationship

   • Requires @JoinTable() to specify the junction table
   • Example: Students and Courses

Cascade operations are configured through the cascade option, with possible values including "insert", "update", "remove", "soft-remove", "recover". For example: @OneToMany(() => Comment, comment => comment.post, { cascade: true })