asp.netentity-framework-migrations

Fatal error encountered during command execution when using command dotnet ef database update


I am trying to set up an C#/ASP.NET project. I am using .Net 9.0.102, VS Code as the IDE and MySql for the database. I installed the Entity Framework, configured the ApplicationDbContext.cs file, and set my database connection string in appsettings.json.

I ran the command dotnet ef migrations add IntialCreate --startup-project examSystem --project examSystem without any issue. My migration file is present along with the ..._InitialCreate.cs file. I then ran the command dotnet ef database update --startup-project examSystem --project examSystem and get the fatal error message.

I don't understand the error message I am receiving and therefore have no clue how to about fixing it.

Here is the error message.

Build started...
Build succeeded.
info: Microsoft.EntityFrameworkCore.Migrations[20411]
      Acquiring an exclusive lock for migration application. See https://aka.ms/efcore-docs-migrations-lock for more information if this takes too long.
Acquiring an exclusive lock for migration application. See https://aka.ms/efcore-docs-migrations-lock for more information if this takes too long.
fail: Microsoft.EntityFrameworkCore.Database.Command[20102]
      Failed executing DbCommand (8ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
      DECLARE @result int;EXEC @result = sp_getapplock @Resource = '__EFMigrationsLock', @LockOwner = 'Session', @LockMode = 'Exclusive';SELECT @result
Failed executing DbCommand (8ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
DECLARE @result int;EXEC @result = sp_getapplock @Resource = '__EFMigrationsLock', @LockOwner = 'Session', @LockMode = 'Exclusive';SELECT @result
fail: Microsoft.EntityFrameworkCore.Database.Command[20102]
      Failed executing DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
      DECLARE @result int;EXEC @result = sp_releaseapplock @Resource = '__EFMigrationsLock', @LockOwner = 'Session';SELECT @result
Failed executing DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
DECLARE @result int;EXEC @result = sp_releaseapplock @Resource = '__EFMigrationsLock', @LockOwner = 'Session';SELECT @result
MySql.Data.MySqlClient.MySqlException (0x80004005): Fatal error encountered during command execution
 ---> MySql.Data.MySqlClient.MySqlException (0x80004005): Parameter '@result' must be defined
   at MySql.Data.MySqlClient.Statement.SerializeParameterAsync(MySqlParameterCollection parameters, MySqlPacket packet, String parmName, Int32 parameterIndex, Boolean execAsync)
   at MySql.Data.MySqlClient.Statement.InternalBindParametersAsync(String sql, MySqlParameterCollection parameters, MySqlPacket packet, Boolean execAsync)
   at MySql.Data.MySqlClient.Statement.BindParametersAsync(Boolean execAsync)
   at MySql.Data.MySqlClient.Statement.ExecuteAsync(Boolean execAsync)
   at MySql.Data.MySqlClient.PreparableStatement.ExecuteAsync(Boolean execAsync)
   at MySql.Data.MySqlClient.MySqlCommand.ExecuteReaderAsync(CommandBehavior behavior, Boolean execAsync, CancellationToken cancellationToken)
   at MySql.Data.MySqlClient.MySqlCommand.ExecuteReaderAsync(CommandBehavior behavior, Boolean execAsync, CancellationToken cancellationToken)
   at MySql.Data.MySqlClient.MySqlCommand.ExecuteReaderAsync(CommandBehavior behavior, Boolean execAsync, CancellationToken cancellationToken)
   at MySql.Data.MySqlClient.MySqlCommand.ExecuteScalarAsync(Boolean execAsync, CancellationToken cancellationToken)
   at MySql.Data.MySqlClient.MySqlCommand.ExecuteScalar()
   at Microsoft.EntityFrameworkCore.Storage.RelationalCommand.ExecuteScalar(RelationalCommandParameterObject parameterObject)
   at MySql.EntityFrameworkCore.Migrations.Internal.MySQLHistoryRepository.AcquireDatabaseLock()
   at MySql.EntityFrameworkCore.Migrations.Internal.MySQLMigrator.Migrate(String targetMigration)
   at Microsoft.EntityFrameworkCore.Design.Internal.MigrationsOperations.UpdateDatabase(String targetMigration, String connectionString, String contextType)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.UpdateDatabaseImpl(String targetMigration, String connectionString, String contextType)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.UpdateDatabase.<>c__DisplayClass0_0.<.ctor>b__0()
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.Execute(Action action)
Fatal error encountered during command execution

Here is my Model with the class to be created in the database.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;

namespace examSystem.Models;

public class Questions
{
    public int Id { get; set; }
    public required string Subject {get; set;}
    public required string ExamQuestion{ get; set; }
    public required string AnswerOption { get; set; }
    public required string CorrectAnswer { get; set; }

    public Questions()
    {
        //constructor
    }
}

Here is my ApplicationDbContext.

using System;
using System.Collections.Generic;
using System.Text;
using examSystem.Models;
using Microsoft.EntityFrameworkCore;



namespace examSystem.Data
{

    public class ApplicationDbContext : DbContext
    {

        public ApplicationDbContext(DbContextOptions options) : base(options)
        {

        }
        public DbSet<Questions> Questions { get; set; }
    }
}

I have not tired anything. I am not understanding the error so I don't know what to try to begin to solve this. I have Googled but what is coming up are stuff pertaining to errors relating to wrong datatype or syntax and not the issue that I am facing.

My expectation is that the database table would have been created and showing in my database.


Solution

  • I had the same problem

    sp_getapplock refers to SqlServer, which suggest that there is a problem with MySql.EntityFrameworkCore 9.0.0

    I saw 2 solutions: 1- Use pre-release version of Pomelo.EntityFrameworkCore.MySql 2- Go back to EF 8

    To play safe in prod, I choose option 2