Question

我遇到了这个问题How to call a stored procedure in EF Core 3.0 via FromSqlRaw。但这不能解决我的问题。我正在使用 MySql数据库。在我的数据库中，有一个存储过程，我在其中插入一些数据，然后返回整个表。

我的存储过程代码类似于：

DELIMITER $$
    Create Procedure InsertDepartments(DName longtext,DLoc longtext)
BEGIN
    INSERT INTO Departments (DepartmentName, DepartmentLocation) 
    VALUES (Dname, DLoc);
    SELECT * FROM Departments ORDER By Departments.DepartmentId DESC;
END$$

如您所见，我正在尝试采用两个参数DName和DLoc。现在在后端的控制器中，我尝试了一些方法：

public JsonResult InsertDepartment([FromBody]Department department)
{
     try
     {
        var deptName = new MySqlParameter("Dname", department.DepartmentName);
        var deptLoc = new MySqlParameter("DLoc", department.DepartmentLocation);

        var departments = _context
          .Departments
          .FromSqlRaw("EXECUTE InsertDepartments @Dname , @DLoc", new object[] {deptName, deptLoc})
          .ToList();
     return Json(departments);
    }
    catch (Exception e)
    {
       return Json(e.Message);
    }
}

但这以某种方式失败了。 PostMan中返回的错误日志是：

"You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ''CSE' , 'DT5'' at line 1"

错误日志：

System.NotSupportedException: Specified method is not supported.
   at System.Text.Json.JsonSerializer.WriteDictionary[TProperty](JsonConverter`1 converter, JsonSerializerOptions options, WriteStackFrame& current, Utf8JsonWriter writer)
   at System.Text.Json.JsonPropertyInfoNotNullable`4.OnWriteDictionary(WriteStackFrame& current, Utf8JsonWriter writer)
   at System.Text.Json.JsonPropertyInfo.WriteDictionary(WriteStack& state, Utf8JsonWriter writer)
   at System.Text.Json.JsonSerializer.HandleDictionary(JsonClassInfo elementClassInfo, JsonSerializerOptions options, Utf8JsonWriter writer, WriteStack& state)
   at System.Text.Json.JsonSerializer.HandleObject(JsonPropertyInfo jsonPropertyInfo, JsonSerializerOptions options, Utf8JsonWriter writer, WriteStack& state)
   at System.Text.Json.JsonSerializer.WriteObject(JsonSerializerOptions options, Utf8JsonWriter writer, WriteStack& state)
   at System.Text.Json.JsonSerializer.Write(Utf8JsonWriter writer, Int32 originalWriterDepth, Int32 flushThreshold, JsonSerializerOptions options, WriteStack& state)
   at System.Text.Json.JsonSerializer.WriteAsyncCore(Stream utf8Json, Object value, Type inputType, JsonSerializerOptions options, CancellationToken cancellationToken)
   at Microsoft.AspNetCore.Mvc.Infrastructure.SystemTextJsonResultExecutor.ExecuteAsync(ActionContext context, JsonResult result)
   at Microsoft.AspNetCore.Mvc.Infrastructure.SystemTextJsonResultExecutor.ExecuteAsync(ActionContext context, JsonResult result)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeResultFilters>g__Awaited|27_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeFilterPipelineAsync>g__Awaited|19_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Logged|17_1(ResourceInvoker invoker)
   at Microsoft.AspNetCore.Routing.EndpointMiddleware.<Invoke>g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger)
   at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)

如何解决此问题？

Answer 1

尝试以下修改：

var deptName = new MySqlParameter("@DName", department.DepartmentName);
var deptLoc = new MySqlParameter("@DLoc", department.DepartmentLocation);

var departments = _context
              .Departments
              .FromSqlRaw("CALL InsertDepartments(@DName,@DLoc)", parameters:new[] { deptName, deptLoc })
              .ToList();

EF Core 3.0存储过程：多个参数

1 个答案: