https://community.abp.io/articles/many-to-many-relationship-with-abp-and-ef-core-g7rm2qut
https://github.com/EngincanV/ABP-Many-to-Many-Relationship-Demo
builder.Entity<BookCategory>(b => { b.ToTable(BookStoreConsts.DbTablePrefix + "BookCategories" + BookStoreConsts.DbSchema); b.ConfigureByConvention(); //define composite key b.HasKey(x => new { x.BookId, x.CategoryId }); //many-to-many configuration b.HasOne<Book>().WithMany(x => x.Categories).HasForeignKey(x => x.BookId).IsRequired(); b.HasOne<Category>().WithMany().HasForeignKey(x => x.CategoryId).IsRequired(); b.HasIndex(x => new { x.BookId, x.CategoryId }); });