Question

我有一个Book类，它在子表中有一个Book Versions。当我正在编写书籍时，BookVersions没有被提取，但是其他相关的表格被提取。我知道你会看到源代码后会说：“默认构造函数在哪里？”但我试图添加它，但它也没有用。

当我尝试手动执行查询时，按预期返回BookVersion。

其他信息：我使用的是MySql.Data.Entity 6.9.3版本，EF6

Sample run

查询以检索数据

选择 Project1。Id， Project1。Name， Project1。AuthorName， Project1。AddedDate， Project1。Active， Project1。C1， Project1。Id1， Project1。VersionName， Project1。BookData， Project1。BookCover， Project1。Active1， Project1。BookId FROM（选择 Limit1。Id， Limit1。Name， Limit1。AuthorName， Limit1。AddedDate， Limit1。Active， Extent2。Id AS Id1， Extent2。VersionName， Extent2。BookData， Extent2。BookCover， Extent2。Active AS Active1， Extent2。BookId， CASE WHEN（Extent2。Id IS NULL）THEN（NULL）ELSE（1）END AS C1 FROM（选择 Extent1。Id， Extent1。Name， Extent1。AuthorName， Extent1。AddedDate， Extent1。Active 来自Books AS Extent1 WHERE 3 = Extent1。Id LIMIT 1）AS Limit1 LEFT OUTER JOIN BookVersions AS Extent2 ON Limit1。Id = Extent2。BookId）AS Project1 订购 Project1。Id ASC， Project1。C1 ASC

- 执行于2014年10月21日09:22:41 +03：00

- 在14毫秒内完成，结果为：EFMySqlDataReader

选择 Extent1。Id， Extent1。VersionName， Extent1。BookData， Extent1。BookCover， Extent1。Active， Extent1。BookId 来自BookVersions AS Extent1 WHERE 3 = Extent1。BookId LIMIT 1

- 执行于2014年10月21日09:22:41 +03：00

- 在7毫秒内完成，结果为：EFMySqlDataReader

选择 Extent1。Id， Extent1。Note， Extent1。StartDate， Extent1。ExpirationDate， Extent1。OwnUserId， Extent1。WhoGaveId， Extent1。BookId 来自UserBooks AS Extent1 WHERE Extent1。BookId = @ EntityKeyValue1

- EntityKeyValue1：＆＃39; 3＆＃39; （Type = Int32）

- 执行于2014年10月21日09:22:50 +03：00

- 在1 ms内完成，结果为：EFMySqlDataReader

源代码如下：

public class Book : BaseEntity
{
    private ICollection<UserBook> _userBook;
    private ICollection<BookVersion> _bookVersions;

    /// <summary>
    /// Gets or sets a value Book name
    /// </summary>
    public string Name { get; set; }
    /// <summary>
    /// Gets or sets a value indicating Book's author name
    /// </summary>
    public string AuthorName { get; set; }
    /// <summary>
    /// Gets or sets a value indicating Book's added date
    /// </summary>
    public DateTime AddedDate { get; set; }
    /// <summary>
    /// Gets or sets a value indicating whether the Book is active
    /// </summary>
    public bool Active { get; set; }
    /// <summary>
    /// Gets or sets who can see the Book
    /// </summary>
    public virtual ICollection<UserBook> UserBooks
    {
        get { return _userBook ?? (_userBook = new List<UserBook>()); }
        set { _userBook = value; }
    }

    /// <summary>
    /// Gets or sets the versions of the Book
    /// </summary>
    public virtual ICollection<BookVersion> BookVersions
    {
        get { return _bookVersions ?? (_bookVersions = new List<BookVersion>()); }
        set { _bookVersions = value; }
    }
}

public class BookVersion : BaseEntity
{

    private Book _book;

    public BookVersion() { }

    /// <summary>
    /// Gets or sets a value indicating VersionName
    /// </summary>
    public string VersionName { get; set; }
    /// <summary>
    /// Gets or sets Book Data.
    /// <remarks>It stores the File as Byte. It is a discrete form of the Book</remarks>
    /// </summary>
    public byte[] BookData { get; set; }
    /// <summary>
    /// Gets or sets a value indicating Book cover
    /// </summary>
    public byte[] BookCover { get; set; }
    /// <summary>
    /// Gets or sets a value indicating whether the version is active
    /// </summary>
    public bool Active { get; set; }
    /// <summary>
    /// Gets or sets a value indicating book identifier
    /// </summary>
    public int BookId { get; set; }
    /// <summary>
    /// Gets or sets the version belongs to whom
    /// </summary>
    public virtual Book OfBook
    {
        get { return _book ?? (_book = new Book()); }
        set { _book = value; }
    }

}

映射是：

public class BookMapping : EntityTypeConfiguration<Book>
{

    public BookMapping()
    {

        this.HasKey(b => b.Id);

        this.Property(b => b.Name).HasMaxLength(255);
        this.Property(b => b.AuthorName).IsOptional();
        this.Property(b => b.AuthorName).HasMaxLength(255);
        this.Property(b => b.Name).IsRequired();
        this.Property(b => b.Active).IsRequired();

    }

}

public class BookVersionMapping : EntityTypeConfiguration<BookVersion>
{

    public BookVersionMapping()
    {

        this.HasKey(n => n.Id);

        this.Property(n => n.BookData).IsRequired();
        this.Property(n => n.VersionName).IsRequired();
        this.Property(n => n.VersionName).HasMaxLength(255);
        this.Property(n => n.BookCover).IsOptional();

        this.HasRequired(bv => bv.OfBook).WithMany(b => b.BookVersions).HasForeignKey(bv => bv.BookId).WillCascadeOnDelete(true);

    }

}

EF6包括不起作用

0 个答案: