我有一个具有复合主键的实体
public class Allocation
{
public Guid WarehouseId { get; set; }
public Guid ProductId { get; set; }
public DateTime Date { get; set; }
public int? Quantity { get; set; }
}
实体配置
public class Allocationconfiguration : IEntityTypeConfiguration<Allocation>
{
public void Configure(EntityTypeBuilder<Allocation> builder)
{
builder.HasKey(e => new { e.WarehouseId,e.ProductId,e.Date }); // Primary key
builder.Property(e => e.Date).HasColumnType("date");
builder.HasOne<Warehouse>().WithMany().HasForeignKey(e => e.WarehouseId);
builder.HasOne<Product>().WithMany().HasForeignKey(e => e.ProductId);
}
}
我可以使用Find
方法来搜索一个实体,该方法接受多个参数作为主键
var allocation = context.Allocations.Find(warehouseId,productId,date);
对于具有一个主键值的实体,我可以使用givenkeys.Contains()
根据主键的集合来搜索多个实体
var keys = new[] { 1,2,3,4 };
var entities = context.Products.Where(product => keys.Contains(product.Id)).ToList();
如何基于多个组合键搜索多个实体?
// Given keys
var keys = new[]
{
new { WarehouseId = warehouse1.Id,ProductId = product1.Id,Date = 12.January(2020) },new { WarehouseId = warehouse1.Id,ProductId = product2.Id,new { WarehouseId = warehouse2.Id,Date = 13.January(2020) },Date = 13.January(2020) }
}