1
我使用实体框架创建代码第一个模型，并在安装第一个版本到客户端后，我们发现数据库的列中有一些变化，我使用实体框架的迁移并且应用所有迁移步骤bat客户端的数据的基础上执行是否实体框架代码在MySql数据库中的第一迁移
Table 'nameTable' already exists
或
Additional information: Duplicate column name 'Reference'
类配置的该代码不存在的最后变化的迁移历史的行和显示此消息
internal sealed class Configuration : DbMigrationsConfiguration<GSM.DataAccess.GSMContext>
{
public Configuration()
{
AutomaticMigrationsEnabled = true;
AutomaticMigrationDataLossAllowed = false;
SetSqlGenerator("MySql.Data.MySqlClient", new MySql.Data.Entity.MySqlMigrationSqlGenerator());
}
protected override void Seed(GSM.DataAccess.GSMContext context)
{
}
}
和类第一迁移
public partial class AddMoreInformationColumn : DbMigration
{
public override void Up()
{
AddColumn("dbo.People", "Reference", c => c.String(unicode: false));
AddColumn("dbo.Products", "Reference", c => c.String(unicode: false));
AddColumn("dbo.Products", "SalePrice", c => c.String(unicode: false));
AddColumn("dbo.Products", "WholePrice", c => c.String(unicode: false));
}
public override void Down()
{
DropColumn("dbo.People", "Address");
DropColumn("dbo.People", "Reference");
DropColumn("dbo.Products", "Reference");
DropColumn("dbo.Products", "SalePrice");
DropColumn("dbo.Products", "WholePrice");
}
}