https://www.yuque.com/yuejiangliu/dotnet/ggh9yb
需要三个包：
dotnet add package Microsoft.EntityFrameworkCore.Design
dotnet add package Pomelo.EntityFrameworkCore.Mysql
dotnet add package Microsoft.EntityFrameworkCore.Tools.DotNet
打开项目文件，在 <ItemGroup /> 中添加一个 <DotNetCliToolReference />：（注意版本号）
<DotNetCliToolReference Include="Microsoft.EntityFrameworkCore.Tools.DotNet" Version="2.0.3" />
dotnet ef dbcontext scaffold
"Server=localhost;Database=sakila;Uid=YourUserName;Pwd=YourUserPassword;SslMode=none"
"Pomelo.EntityFrameworkCore.MySql" -d -f -o Models
dotnet ef dbcontext scaffold
"Server=192.168.7.11;Database=sakila;uid=sa;pwd=YourUserPassword;"
"Microsoft.EntityFrameworkCore.SqlServer" -d -f -o Models
链接字符串：mysql：Server=localhost;Database=sakila;Uid=YourUserName;Pwd=YourUserPassword;SslMode=none
sqlserver：DataSource=LocalHost;Database=sakila;Uid=YourUserName;Pwd=YourUserPassword;