Question

我正在尝试使用命令dotnet ef migrations script，以便在上次应用的迁移和最后一次未应用的迁移之间创建SQL脚本。应用迁移是一种称为dotnet ef database update

的迁移

我尝试执行以下命令，但它们都不起作用：

dotnet ef  --startup-project ../DbMigrations/ migrations script from LastAppliedMigration to LastNotAppliedMigration -o temp.sql --context MyProject.DbModel.MusicDbContext

dotnet ef  --startup-project ../DbMigrations/ migrations script from LastAppliedMigration -o temp.sql --context MyProject.DbModel.MusicDbContext

我收到以下错误： System.InvalidOperationException：迁移＆＃39;来自＆＃39;没找到。

System.InvalidOperationException: The migration 'from' was not found.
   at Microsoft.EntityFrameworkCore.Migrations.MigrationsAssemblyExtensions.GetMigrationId(IMigrationsAssembly assembly, String nameOrId)
   at Microsoft.EntityFrameworkCore.Migrations.Internal.Migrator.GenerateScript(String fromMigration, String toMigration, Boolean idempotent)
   at Microsoft.EntityFrameworkCore.Design.MigrationsOperations.ScriptMigration(String fromMigration, String toMigration, Boolean idempotent, String contextType)
   at Microsoft.EntityFrameworkCore.Tools.Cli.MigrationsScriptCommand.Execute(CommonOptions commonOptions, String from, String to, String output, Boolean idempotent, String context, String environment)
   at Microsoft.EntityFrameworkCore.Tools.Cli.MigrationsScriptCommand.<>c__DisplayClass0_0.<Configure>b__0()
   at Microsoft.Extensions.CommandLineUtils.CommandLineApplication.Execute(String[] args)
   at Microsoft.EntityFrameworkCore.Tools.Cli.Program.Main(String[] args)

对于迁移名称，我尝试了两个版本的前缀为timestamp且没有：

20160920085915_LastAppliedMigration
LastAppliedMigration

我是否正确使用此命令dotnet ef migrations script？

修改1

我做了一个简单的例子来证明我的问题。该示例可以从这里下载Download example

我做了什么：

创建了默认的Web应用程序项目
dotnet ef migrations add Initial
dotnet ef migrations script -o initial.sql - 创建了initial.sql文件
dotnet ef database update
在Student

Data

添加了``DbSet in ApplicationDbContext```
dotnet ef migrations add Student
dotnet ef migrations script from 20160924174811_Initial -o student.sql

这里我收到以下错误 - 来自＆＃39;的迁移＆＃39;没找到。

Project WebApplication3 (.NETCoreApp,Version=v1.0) was previously compiled. Skipping compilation.              
System.InvalidOperationException: The migration 'from' was not found.                                          
   at Microsoft.EntityFrameworkCore.Migrations.MigrationsAssemblyExtensions.GetMigrationId(IMigrationsAssembly assembly, String nameOrId)                                                                                     
   at Microsoft.EntityFrameworkCore.Migrations.Internal.Migrator.GenerateScript(String fromMigration, String to Migration, Boolean idempotent)                                                                                 
   at Microsoft.EntityFrameworkCore.Design.MigrationsOperations.ScriptMigration(String fromMigration, String to Migration, Boolean idempotent, String contextType)                                                             
   at Microsoft.EntityFrameworkCore.Tools.Cli.MigrationsScriptCommand.Execute(CommonOptions commonOptions, String from, String to, String output, Boolean idempotent, String context, String environment)                     
   at Microsoft.EntityFrameworkCore.Tools.Cli.MigrationsScriptCommand.<>c__DisplayClass0_0.<Configure>b__0()   
   at Microsoft.Extensions.CommandLineUtils.CommandLineApplication.Execute(String[] args)                      
   at Microsoft.EntityFrameworkCore.Tools.Cli.Program.Main(String[] args)                                      
The migration 'from' was not found.

当我dotnet ef migrations list时，我得到以下结果：

Project WebApplication3 (.NETCoreApp,Version=v1.0) was previously compiled. Skipping compilation.
20160924174811_Initial
20160924175511_Student

CLI工具的版本是

dotnet --version
1.0.0-preview2-003131

Answer 1

好的我明白了。

from不是选项名称，其位置应直接来自迁移名称。

下面的工作命令示例：

dotnet ef migrations script Initial -o student.sql

或也有效

dotnet ef migrations script 20160924174811_Initial -o student2.sql

使用ASP.NET Core工具创建迁移脚本时未找到迁移

1 个答案: