必须在SQL SERVER和C中声明标量变量#

我这里有一个方法，通过代码传递sql字符串并获取值。这是失败的，我想通过查看sql资源管理器本身中传递的sql来了解原因

这就是整个方法，您可以看到它从正在创建的“new”对象获取“@”值

        var rowsUpdated = await this.repository.ExecuteAsync(
                @"merge into MyTable WITH (HOLDLOCK) as dst
                    using (select @id as M_id,  
                        @username as Username, 
                        @emailVerificaton as EmailVerification, 

                    ) as src on dst.M_id = src.M_id and dst.Username = src.Username
                when matched then 
                    update set dst.EmailVerification = src.EmailVerification,

                when not matched then
                    insert(M_id, Username, EmailVerification) 
                    values(src.M_id, src.Username, src.EmailVerification);", new
                {
                    id = id, //e.g 1
                    username = username, //e.g "dros"
                    emailVerificaton = emailVerificaton, //e.g true

                })

当我尝试运行此sql代码时：

                merge into MyTable WITH (HOLDLOCK) as dst
                    using (select @id as M_id,  
                        @username as Username, 
                        @emailVerificaton as EmailVerification, 

                    ) as src on dst.M_id = src.M_id and dst.Username = src.Username
                when matched then 
                    update set dst.EmailVerification = src.EmailVerification,

                when not matched then
                    insert(M_id, Username, EmailVerification) 
                    values(src.M_id, src.Username, src.EmailVerification)

我收到这样的投诉：

必须声明标量变量“@username”

---

不确定如何传入这些变量，我尝试的所有操作都会导致语法错误

在SSMS中，在merge语句之前声明@id int=1（etc）。或者甚至更基本的（仅用于测试）将参数替换为文字值，如EmailVerification、和

更新集dst.EmailVerification=src.EmailVerification、

，否则看起来是正确的，假设您使用的是Dapper。如果您试图在SSMS中运行它，您可以在包含值之前放置

declare

语句