Entity Framework 6 Code First +MVC5+MySql/Oracle使用过程中的几个问题

1、

namespace Snapsia.Web.Models
{
    using System;
    using System.Data.Entity;
    using System.ComponentModel.DataAnnotations.Schema;
    using System.Linq;

    [DbConfigurationType(typeof(MySql.Data.Entity.MySqlEFConfiguration))]
    public partial class SnapsiaContext : DbContext
    {
        public SnapsiaContext()
            : base("name=SnapsiaContext")
        {
        }

        public virtual DbSet<InfluencersUser> InfluencersUser { get; set; }
        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
        }
    }
}

2、表“TableDetails”中列“IsPrimaryKey”的值为 DBNull

解决办法：

set global optimizer_switch='derived_merge=OFF';

 http://stackoverflow.com/questions/33575109/mysql-entity-the-value-for-column-isprimarykey-in-table-tabledetails-is

http://bugs.mysql.com/bug.php?id=79163

https://dev.mysql.com/doc/refman/5.7/en/switchable-optimizations.html

3、

[Table("TB_USER", Schema = "USER_SNAPSIA")]//dbo架构在oracle数据库为用户名
    public partial class TB_USER
    {
        [Key]
        [StringLength(50)]
        public string ID { get; set; }

        [StringLength(50)]
        public string USERNAME { get; set; }

        [StringLength(50)]
        public string PWD { get; set; }
    }

public partial class OrclContext : DbContext
    {
        public OrclContext()
            : base("name=OrclContext")
        {
        }
        public virtual DbSet<TB_USER> TB_USER { get; set; }
        public virtual DbSet<TB_SYYS> TB_SYYS { get; set; }
        public virtual DbSet<TB_CCT> TB_CCT { get; set; }

        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            modelBuilder.HasDefaultSchema("USER_SNAPSIA"); //dbo架构在oracle数据库为用户名

            modelBuilder.Entity<TB_USER>()
                .Property(e => e.ID)
                .IsUnicode(false);
        }
    }

4、VS2015 update3 +MySQL5.7+EntityFramework Code First 

从数据库生成Code First 代码，选择连接后点击下一步，界面闪退，无法生成的解决办法。

需要安装最新版的两个组件：

mysql-connector-net-6.9.9 

mysql-for-visualstudio-1.2.6

5、使用同一个上下文对象：

public static SnapsiaContext GetCurrentDbSession()
{
    SnaContext context = CallContext.GetData(typeof(DbSessionContextFactory).FullName) as SnaContext;
    if (context == null)
    {
         context = new SnaContext();
         CallContext.SetData(typeof(DbSessionContextFactory).FullName, context);
    }
    return context;
}

6、EntityFramework Code First 优化

6.1、推荐使用IIS8.

6.2、参考文章：亲授MVC5中EF6 Code First启动慢及间隙变慢优化的实践经验

https://weblog.west-wind.com/posts/2013/Oct/02/Use-IIS-Application-Initialization-for-keeping-ASPNET-Apps-alive?utm_source=tuicool#GettingstartedwithApplicationInitialization

http://www.cnblogs.com/hantianwei/archive/2013/04/26/3044157.html