无法将代码首次迁移到mysql数据库 [英] Unable to apply code first migrations to mysql database

问题描述

我正在使用EF代码第一模型在asp.net mvc上工作。我试图使用EF代码首先应用迁移到我的项目。我正在使用MySql数据库。目前我使用的是EF 4.3.1版本和6.6.4.0版本的mysql连接器/ .net。我成功地将迁移添加到我的项目中，这意味着我执行一系列不给我错误的命令。我已经按照这些步骤，

  PM>启用迁移
 
 PM>添加迁移初始迁移
 
 PM> update-database -verbose 
  

这些步骤将Migration文件夹创建到我的项目，并在Migration文件夹中创建配置timestamp_Initialmigration文件，在配置文件中我添加了以下代码。

  SetSqlGenerator（MySql.Data.MySqlClient，新的MySql.Data .Entity.MySqlMigrationSqlGenerator（））; 
  

之后，我已经将一个字段添加到我的课堂，如

  public int newprop {get; set;} 
  

之后，我在PM控制台中执行update-database -verbose命令。

当我执行我的应用程序时，会抛出一个错误，如

未知列'Extent1.newprop'字段列表'

请指导我为什么我得到这个错误我去错了的方式请指导我。

解决方案

如果您不使用自动迁移

Database.SetInitializer（new MigrateDatabaseToLatestVersion（））; / p>

  public class MyMigrationConfiguration：DbMigrationsConfiguration< MyDbContext> 
 {
 public MyMigrationConfiguration（）
 {
 AutomaticMigrationsEnabled = true;你在用这个
 AutomaticMigrationDataLossAllowed = true; 
} 
} 
  

然后，您需要使用PM Commandlet添加另一个迁移并更新数据库。

  PM>启用迁移//已经完成了？ 
 PM>添加迁移myLabel 
 PM>更新数据库
  

在网络上搜索基于代码的迁移以获取帮助

I am working on asp.net mvc with EF code first model. I am trying to apply migrations using EF code first to my project. I am using MySql database. currently i am using EF 4.3.1 version and mysql connector/.net of 6.6.4.0 version. I am successfully add migrations to my project that means i execute series of commands that gave no errors for me. I have followed these steps,

PM> Enable-Migrations

PM> Add-Migration InitialMigration

PM> update-database -verbose

these steps create Migration folder to my project and inside Migration folder it creates configuration and timestamp_Initialmigration files, in configuration file i have added following code.

SetSqlGenerator("MySql.Data.MySqlClient", new MySql.Data.Entity.MySqlMigrationSqlGenerator());

after that i have added one field to my class like,

public int newprop{get; set;}

after that i execute update-database -verbose command in PM console.

when i execute my application it throws an error like,

"Unknown column 'Extent1.newprop' in 'field list'"

please guide me why i am getting this error does i went to the wrong way please guide me.

解决方案

If your not using automatic migrations

Database.SetInitializer(new MigrateDatabaseToLatestVersion());

 public class MyMigrationConfiguration : DbMigrationsConfiguration<MyDbContext>
    {
        public MyMigrationConfiguration()
        {
            AutomaticMigrationsEnabled = true; // Are you using this ?????
            AutomaticMigrationDataLossAllowed = true;
        }
    }

Then you need to tell EF using the PM Commandlet to add another migration and update the database.

PM> Enable-Migrations  //already done this ?
PM> Add-Migration myLabel
PM> Update-Database

Search for "code based migrations" on web for help

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