MySQL Forums - Connector/NET and C#, Mono, .Net

Clientless connection with PS (no replies)

Emmanuel BILLOT — Tue, 05 May 2026 20:45:19 +0000

Hi,

Is there anyway to query a MySQL server from en Windows client in PowerShell WITHOUT installing any software/driver on it ?

We wander if it is possible to execute a light PowerShell script from any client connected to the network, from a share, making some select and insert, but with no MySQL connector install.

Using "[void][system.reflection.Assembly]::LoadFrom" we got errors, and no cmdlets recognized.

One "dirty" way should use a mysql.exe from a share, but results are unusable.

Could it be possible to "load" MySQL libs or cmd "on the fly" with no install on the computer executing the powershell script ?

Regards,

Is there a 64-bit version of MySQL Connector/NET 9.4.0 available? (no replies)

Muhammed Dhanish — Wed, 03 Sep 2025 08:22:24 +0000

Hello,

I am trying to connect Power BI (64-bit) to my MySQL database. Currently, I can connect using the MySQL ODBC 9.4 Unicode Driver, but I wanted to check if there is a 64-bit version of MySQL Connector/NET 9.4.0 available.

On the official download page, I only see a 32-bit installer. Will there be a 64-bit release of Connector/NET 9.4.0, or is ODBC the only option for Power BI connections at the moment?

MySqlConnectionStringBuilder CharacterSet Property (no replies)

Ben Hagley — Thu, 31 Jul 2025 15:24:02 +0000

Hi

I have a ASP.Net core web app hosted in Azure connected to a Azure MySQL Flexible Server. The web app is utilising MySql.EntityFrameworkCore (8.0.14).

The MySQL connection string is built using MySqlConnectionStringBuilder.

When updating or adding EF Core entities that contain unicode characters (for our Translations data), the rows in the MySQL table contain question marks instead of the unicode data.

I have found the MySqlConnectionStringBuilder property CharacterSet. The documentation says the following for this property....

Supported for backwards compatibility; MySqlConnector always uses utf8mb4

When I do not set this property, I get the question marks in the database, but when specifically setting it to "utf8mb4" the data is created correctly.

I have two questions....
1) Why do I need to set the CharacterSet to "utf8mb4" if it should be the default?
2) Is there anyway I can determine in code what the CharacterSet is when I do not set the property. (When checking the property on MySqlConnectionStringBuilder in debug it is a blank string)

Thanks

Connector/Net and SSIS (no replies)

Phillip Doughty — Thu, 24 Jul 2025 13:39:38 +0000

Hi,

I am using sql server integration services and the Connector/NET to extract data from 2 mysql sources.

1. AWS Aurora (MySQL Version 8.0.36)
2. Magento Cloud (MariaDB)

What I am struggling with is they work with different Connector Versions. I need to run my connections with AWS Aurora with mysql-connector-net-8.0.32. Magento Cloud runs with mysql-connector-net-9.1.0

On my server, I cannot run both versions so I have to keep swapping versions or run on different servers.

Does anyone have any suggestions on how I could get them to coexist ?

Thanks

Upgraded Connector/NET from 8.0.32 to 9.3.0 get error connecting (no replies)

Abdulaziz Loonat — Thu, 19 Jun 2025 14:42:25 +0000

Using Windows 10 MS PowerBI to connect to a MySQl database

Our vulnerability scanner (Qualys) detected Connector/NET v8.0.32 to be vulnerable and needed to upgrade to v9.3.0

I did this and now I am unable to connect to the database. Was working on previous version.

Get error This connector requires one or more additional components to be installed before it can be used

I am sure I am missing some other components in Windows, I assume its .NET versions I am missing or some other component.

Any ideas

MySql.EntityFrameworkCore 8.0.8 RenameColumnbug (no replies)

live tony — Tue, 19 Nov 2024 07:31:38 +0000

I am using MySql.EntityFrameworkCore 8.0.8 and encounter an error when dealing with RenameColumn, similar to the following link:
https://stackoverflow.com/questions/78445536/c-sharp-and-entityframworkcore-error-after-running-dotnet-ef-database-update

Request: Better migration exception messages (no replies)

Neil Scales — Wed, 16 Oct 2024 15:57:00 +0000

I've just swapped my project from Pomelo to MySql.EntityFrameworkCore 8.0.5, and created a brand new migration.

When running the migration I get this exception:

MySql.Data.MySqlClient.MySqlException : BLOB, TEXT, GEOMETRY or JSON column 'name' can't have a default value
MySqlStream.ReadPacketAsync(Boolean execAsync)
NativeDriver.GetResultAsync(Int32 affectedRow, Int64 insertedId, Boolean execAsync)
Driver.GetResultAsync(Int32 statementId, Int32 affectedRows, Int64 insertedId, Boolean execAsync)
Driver.NextResultAsync(Int32 statementId, Boolean force, Boolean execAsync)
MySqlDataReader.NextResultAsync(Boolean execAsync, CancellationToken cancellationToken)
MySqlDataReader.NextResultAsync(Boolean execAsync, CancellationToken cancellationToken)
MySqlCommand.ExecuteReaderAsync(CommandBehavior behavior, Boolean execAsync, CancellationToken cancellationToken)
MySqlCommand.ExecuteReaderAsync(CommandBehavior behavior, Boolean execAsync, CancellationToken cancellationToken)
MySqlCommand.ExecuteReaderAsync(CommandBehavior behavior, Boolean execAsync, CancellationToken cancellationToken)
MySqlCommand.ExecuteNonQueryAsync(Boolean execAsync, CancellationToken cancellationToken)
MySqlCommand.ExecuteNonQuery()
RelationalCommand.ExecuteNonQuery(RelationalCommandParameterObject parameterObject)
MigrationCommand.ExecuteNonQuery(IRelationalConnection connection, IReadOnlyDictionary`2 parameterValues)
MigrationCommandExecutor.ExecuteNonQuery(IEnumerable`1 migrationCommands, IRelationalConnection connection)
Migrator.Migrate(String targetMigration)
RelationalDatabaseFacadeExtensions.Migrate(DatabaseFacade databaseFacade)

I have 300 tables, so which table with a column "name" has failed?

Also, all these tables previously had default values, so why doesn't the net8 driver allow it?

Error: Data index must be a valid index in the field (no replies)

Stanley Roper — Sat, 05 Oct 2024 11:52:12 +0000

I'm using the MySQL Connector/NET driver with the SQL Server Import and Export Wizard to transfer data from a MySQL 5.7 database to SQL Server. There's one particular table (named "datablob") that contains thirty gigabytes of longblob data (about 24K records). After several seconds into the transfer, it stops with the following error:

Error 0xc020f444: Data Flow Task 1: The error "Data index must be a valid index in the field" occurred while processing "Source - datablob.Outputs[ADO NET Source Output].Columns[data]".

Does anyone know what this error means and how to fix? Is the problem with a particular record in the table, a configuration setting with the driver, or a bug?

Thank you!

Timeout period elapsed prior to obtaining a connection from the pool - Azure Flexible MySQL (no replies)

Jess Pomfret — Thu, 12 Sep 2024 12:00:19 +0000

The MySQL instance was automigrated from a single server to a flexible server this morning.

The .NET client was updated from 8.0.21 to 9.0.0 as we were hitting errors that we couldn't connect, which made sense since flexible server required at least 8.0.32.

Since then we found that active connections were increasing close to 300 (which is what we have max_connections set to). We then found wait_timeout has changed from single (120 seconds we think) to 8 hours. We set this value to 120 on the new flexible server. Connections then levelled out - and are around 60-70.

However, we are still getting the following error:

An Exception Occurs In AuthenticateController.ObtainToken.
Exception Thrown: Exception: MySql.Data.MySqlClient.MySqlException (0x80004005): error connecting: Timeout expired.
The timeout period elapsed prior to obtaining a connection from the pool. This may have occurred because all pooled connections were in use and max pool size was reached.

Any ideas? Or places to look for troubleshooting?

Concurrency Check issue with EF Core 8 (Regression from 6) (1 reply)

Ryan Kelly — Wed, 16 Oct 2024 16:21:41 +0000

I have been working on porting an EF implementation over to EF Core, I noticed that a fairly important use case for us, Concurrency Checking, wasn't working as expected, the underlying value had not changed but it stopped returning the expected concurrency error that our application depends heavily upon.

Having dug into this I've created what I feel to be a really minimal reproduction of the issue which follows

https://github.com/rtkelly13/MySQLEFConcurrencyBug

By adapting and simplifying the current Concurrency test in the MySQL repository. Hopefully my reproduction of both the behaviour on 6 and 8 will help identify the issue.
I hadn't got far enough to copy the source and attempt to compile it myself, I managed to debug the EF Core code up to the MySQL layer using Rider

Tested on the mysql:8.0 docker image running locally.

I have a problem querying a date with connector 8.0.17 (no replies)

Ernesto Peralta — Fri, 19 Jul 2024 12:33:10 +0000

i have this code in the start of my project

System.Threading.Thread.CurrentThread.CurrentCulture=System.Globalization.CultureInfo.CreateSpecificCulture("es-DO")
System.Globalization.DateTimeFormatInfo.CurrentInfo.ShortDatePattern = "dd'/'MM'/'yyyy"

The problem is that my application handles the date in "dd/MM/yyyy" format, when I query a date with connector 8.0.16 or lower, it doesn't matter if it is from a stored procedure or a simple select, the date comes in "dd/MM/yyyy" format, but from version 8.0.17 to the most recent 9.0.0 when I consult a date it has the format "MM/dd/yyyy" causing errors in my program.

Is there a way to configure the connector's date format, or the connector's culture?

Thank you!

MySql 8.4 Parameter with DbNull.Value problems (no replies)

Jefferson Manske — Fri, 28 Jun 2024 20:21:23 +0000

We are experiencing issues across various tables, with different fields, where randomly the value 2024 is being recorded in the column when passing the parameter as shown below. This occurs only when the instruction "IIf(iAnyID2 = 0, DBNull.Value, iAnyID2)" is used, even though the value of the property iAnyID2 is zero by default and the value is not assigned anywhere.

myCmd.Parameters.AddWithValue("@AnyID2", IIf(iAnyID2 = 0, DBNull.Value, iAnyID2))

It does not always record the value 2024; sometimes it correctly records NULL.

MySQL 8.0: Connector/NET - SecureString (3 replies)

Paul Haynes — Mon, 17 Jun 2024 18:57:22 +0000

Hello

I was wondering whether there was any plans on your roadmap to support using the SecureString class for managing a connection string in a similar way to that which is possible with the SqlConnection object in the .Net libraries?

Trying to see how it is possible for that connection string to not be available in memory on a client-side application but as the MySQLConnection class has it's connection string as a normal string - this is always going to be available plaintext.

Many thanks

Issues on MySQL for Excel (2 replies)

Iván Ríos Gracia — Mon, 20 May 2024 09:28:32 +0000

So I'm having quite of an problem with an specific case.
Got a worksheet that I share with people. The requirements for this to work is to have MySQL for Excel 8.3 + Connector/Net 8.3.

On the machine where I created the template, after putting it up on a cloud and downloading it, I got no issue.

But when I try to get that same file on another machine with al requirements installed correctly, I get a window that says "Excel Tables Reconnection". If it only appears the first time and after putting the connection credentials is not appearing anymore there will be not a problem. But after you put the connection credentials correctly, save it, closing it and opening it back, "Excel Tables Reconnection" window appears again and it forces you to create once more a connection you already have saved. And there's no option to select an existing one, it just let you create or delete all.

How can I fix this issue?

Fatal error encountered attempting to read the resultset after 1 hour (no replies)

erdem yalçın — Wed, 08 May 2024 12:14:48 +0000

I have a code piece to run a stored procedure in mysql. Code runs and completes when execution time is under 1 hour however when it takes more than 1 hour it gets an exception. I set command timeout to 7200 and I also tried to increase various other timeout parameters in code with following queries without any success:

SET SESSION wait_timeout=99999; SET SESSION interactive_timeout=99999;
set net_write_timeout=99999; set net_read_timeout=99999

When I use Dbeaver client procedure completes even if it takes more than 1 hour.

I'm using Mysql.Data version: 8.4. Mysql database version is:8.0.32

Code it as follows:

string sql = "EDW.SP_DENEME_20240503";
string connStr = @"Server=hostname;Port=port; Database=;Uid=xxxx;Pwd=pwd;AllowLoadLocalInfile=true;allowPublicKeyRetrieval=true;Connect Timeout=120";
using (var conn = new MySqlConnection(connStr))
using (MySqlCommand cancellableCommand = new MySqlCommand(sql, conn))
{
cancellableCommand.CommandTimeout = 7200;
cancellableCommand.CommandType = CommandType.StoredProcedure;

cancellableCommand.Parameters.Add(new MySqlParameter("v_ASOFDATE", 20240421));
cancellableCommand.Parameters.Add(new MySqlParameter("v_LOGTYPE", "M"));
conn.Open();
OpenConnection(conn, connectionRetryCount);
return cancellableCommand.ExecuteNonQuery();
}

Error message:

Exception msg :Fatal error encountered during command execution.
Exception inner exc :Fatal error encountered attempting to read the resultset.
Exception stacktrace : at MySql.Data.MySqlClient.MySqlCommand.d__111.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at MySql.Data.MySqlClient.MySqlCommand.d__111.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at MySql.Data.MySqlClient.MySqlCommand.d__100.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at MySql.Data.MySqlClient.MySqlCommand.ExecuteNonQuery()

I would appreciate any suggestions regarding the issue.

A null was returned after calling the 'GetService' method on a store provider instance of type 'MySql.Data.MySqlClient.MySqlClientFactory' (no replies)

Venkata Ramana Raju — Fri, 03 May 2024 11:28:49 +0000

I recently upgraded my database from mySql 5.5 to mySQL 8.0.27, mySQL .NET Connector 8.0.27 & Entity Framework from 5 to 6.4.4. Now when making a DB call from code using EF, I am receiving the error "System.Data.ProviderIncompatibleException: A null was returned after calling the 'GetService' method on a store provider instance of type 'MySql.Data.MySqlClient.MySqlClientFactory'. The store provider might not be functioning correctly."

Source is "System.Data.Entity".

I am using VS 2022 & .Net framework is 4.8.

Can any one please suggest where I am missing?

HResult=0x80131501 on my new Win11 32bit machine (no replies)

Jon Jacobs — Thu, 25 Apr 2024 17:13:17 +0000

This the closest match I could find to post my query, although connector is not explicit in the code. Note: ctor in code below refers to the constructor.
When I login to MySQL 8.3 Command Line Client, I get no error. The connection works fine in HeidiSQL also. When I run my code programatically I get the error.
Message=A call to SSPI failed, see inner exception.
Source=MySql.Data
Inner Exception 1:
Win32Exception: The message received was unexpected or badly formatted
Here is the code:
public void MakeConnection()
{
string connectionstring = "Server=localhost; UID=root; Pwd=; Database=MyDatabase;";
con = new MySqlConnection(connectionstring);
if (con == null) return;
con.Open();
cmd = con.CreateCommand();
}
It throws the error at con.Open(); Interestingly, when I run the exact same code on my Win 8.1 32bit machine, I get no error. Obviously a different instance of MySQL, since both are localhost.
The password is NOT misspelled. Re-typed numerous times in program and command line to be sure.
Here is the stack trace for the error in case that helps:
StackTrace:
at MySql.Data.Common.Ssl.StartSSL(Stream& baseStream, Encoding encoding, String connectionString)
at MySql.Data.MySqlClient.NativeDriver.Open()
at MySql.Data.MySqlClient.Driver.Open()
at MySql.Data.MySqlClient.Driver.Create(MySqlConnectionStringBuilder settings)
at MySql.Data.MySqlClient.MySqlPool.CreateNewPooledConnection()
at MySql.Data.MySqlClient.MySqlPool.GetPooledConnection()
at MySql.Data.MySqlClient.MySqlPool.TryToGetDriver()
at MySql.Data.MySqlClient.MySqlPool.GetConnection()
at MySql.Data.MySqlClient.MySqlConnection.Open()
at DB.BaseDB.MakeConnection() in C:\Users\jonqj\Projects\DB\BaseDB.cs:line 112
at DB.BaseDB..ctor(String cns) in C:\Users\jonqj\Projects\DB\BaseDB.cs:line 100
at MYSQL.MySQL..ctor(String cns) in C:\Users\jonqj\Projects\MYSQL\MySQL.cs:line 14
at ConsoleApp1.Program.Main(String[] args) in C:\Users\jonqj\Projects\ConsoleApp1\Program.cs:line 12

I am in the process of migrating lots of stuff from my win 8.1 machine to my win 11 machine.
What can I do to make this work? Thank you.

System.AggregateException: One or more errors occurred. (1 reply)

Роман Берлов — Thu, 24 Oct 2024 03:35:04 +0000

I use MySql.Data 8.3.0 version for NET 8.0.

I call asynchronous methods but I don't use async void only async Task. But my try-catches do not work, I get this error in AppDomain.CurrentDomain.UnhandledException event handler:

System.AggregateException: One or more errors occurred. (Authentication to host '142.132.202.107' failed. (I/O error occurred.))
---> System.AggregateException: Authentication to host '142.132.202.107' failed. (I/O error occurred.)
---> System.IO.IOException: I/O error occurred.
--- End of inner exception stack trace ---
at MySql.Data.Common.Ssl.b__10_1()
at System.Threading.CancellationTokenSource.Invoke(Delegate d, Object state, CancellationTokenSource source)
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
--- End of stack trace from previous location ---
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.CancellationTokenSource.ExecuteCallbackHandlers(Boolean throwOnFirstException)
--- End of inner exception stack trace ---
at System.Threading.CancellationTokenSource.ExecuteCallbackHandlers(Boolean throwOnFirstException)
at System.Threading.TimerQueueTimer.Fire(Boolean isThreadPool)
at System.Threading.TimerQueue.FireNextTimers()
at System.Threading.ThreadPoolWorkQueue.Dispatch()
at System.Threading.PortableThreadPool.WorkerThread.WorkerThreadStart()

Also, I'm disappointed because my code is missing in the stack trace. I don't understand - it may be a bug or not that I don't handle Exception into my catch block.

MySql.EntityFrameworkCore No DbUpdateConcurrencyException thrown when concurrency conflictis expected (1 reply)

zhenhua li — Tue, 30 Jul 2024 08:38:39 +0000

When using MySql When the EntityFrameworkCore connects to MySQL, it does not throw the DbUpdateConcurrencyException exception when there is concurrency in updating data
The code is as follows

Services AddDbContext（

(sp, optionsBuilder)=>
{
OptionsBuilder UseMySQL (connectionString)
. Enabling DetailedErrors ()
. enableSensitiveDataLogging();
});

[Table ("user_count2")]
Public class UserAccount
{
[Column ("id")]
Public int Id {get; set;}

[Column ("user_id")]
Public int? UserId {get; set;}

[StringLength (11)]
//[Comment ("Account Name")]
[Column ("account name")]
Public string AccountName {get; set;}

//[Comment ("Creation Time")]
[Column ("create-time")]
Public DateTime? Create Time {get; set;}

[Column ("is_delete")]
Public int? IsDelete {get; set;}

[Column ("delete-time")]
Public DateTime? DeleteTime {get; set;}

[Column ("version", TypeName="varchar")]
//[Timestamp]
[ConcurrencyCheck]
//[Timestamp]
Public Guid Version {get; set;}

[Column (name: "createat", TypeName="timestamp")]
Public DateTime? Create At {get; set;}
}
UserAccount? UserAccount=testContext UserAccounts Find (100003);
//Console WriteLine (userAccount. CreateAt?. ToString ("yyyy MM dd HH: mm: ss. fff: ffffff"));
Try
{
UserAccount AccountName="atest";
UserAccount Version=Guid NewGuid();
UserAccount Create At=DateTime UtcNow;
TestContext UserAccounts Update (userAccount);
Int rows=testContext SaveChanges ();
Console WriteLine (rows);
}
Catch (DbUpdateConcurrencyException ex)
{

Throw ex;
}
The execution result always returns 1, and no DbUpdateConcurrencyException exception was thrown

MySql.EntityFrameworkCore No DbUpdateConcurrencyException thrown when concurrency conflictis expected (no replies)

zhenhua li — Thu, 11 Apr 2024 02:03:51 +0000

当使用 MySql.EntityFrameworkCore 连接mysql 时候，更新数据出现并发的时候也没有抛出 DbUpdateConcurrencyException 异常信息
,代码如下

services.AddDbContext(

(sp,optionsBuilder) =>
{
optionsBuilder.UseMySQL(connectionString)
.EnableDetailedErrors()
.EnableSensitiveDataLogging();
});

[Table("user_account2")]
public class UserAccount
{
[Column("id")]
public int Id { get; set; }

[Column("user_id")]
public int? UserId { get; set; }

[StringLength(11)]
//[Comment("账号名称")]
[Column("account_name")]
public string AccountName { get; set; }

//[Comment("创建时间")]
[Column("create_time")]
public DateTime? CreateTime { get; set; }

[Column("is_delete")]
public int? IsDelete { get; set; }

[Column("delete_time")]
public DateTime? DeleteTime { get; set; }

[Column("version", TypeName = "varchar")]
//[Timestamp]
[ConcurrencyCheck]
//[Timestamp]
public Guid Version { get; set; }

[Column(name: "create_at", TypeName = "timestamp")]
public DateTime? CreateAt { get; set; }
}
UserAccount? userAccount = testContext.UserAccounts.Find(100003);
//Console.WriteLine(userAccount.CreateAt?.ToString("yyyy-MM-dd HH:mm:ss.fff:ffffff"));
try
{
userAccount.AccountName = "atest";
userAccount.Version = Guid.NewGuid();
userAccount.CreateAt= DateTime.UtcNow;
testContext.UserAccounts.Update(userAccount);
int rows= testContext.SaveChanges();
Console.WriteLine(rows);
}
catch (DbUpdateConcurrencyException ex)
{

throw ex;
}
执行结果永远都还返回是1，没有抛出 DbUpdateConcurrencyException 异常

Problem my MYSQL connector (no replies)

Alexis Blanco — Mon, 08 Apr 2024 11:03:31 +0000

Hello,

I have been using Microsoft POWER BI for a while to analyze data taken directly from a MySQL DB. In order to get data from MySQL it is necessary to download and install a connector:
https://dev.mysql.com/downloads/connector/net/
I had several reports up and running. They were refreshing automatically from POWER BI Service using a personal mode gateway.

After some problems trying to configure a new report I uninstalled and intalled the conector among other things. Right now I can't connect at all to MySQL from POWER BI, as even the desktop version says it did not find the necessary connector.

In this link https://learn.microsoft.com/en-us/power-query/connectors/mysql-database it is mentioned to do the following operation to check if the connector is correctly installed.:
"The MySQL connector requires the MySQL Connector/NET package to be correctly installed. To determine if the package has installed correctly, open a PowerShell window and run the following command:

[System.Data.Common.DbProviderFactories]::GetFactoryClasses()|ogv"

Which gives me the following error:

"Exception when calling "GetFactoryClasses" with arguments "0": "An error occurred while creating the configuration section handler for system.data: The column 'InvariantName' is restricted to be unique. The value 'is already present Mysql.Data.MySqlClient'. (C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Config\machine.config line 157)"
En línea: 1 Carácter: 1
+ [System.Data.Common.DbProviderFactories]::GetFactoryClasses()|ogv
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : NotSpecified: (:) [], MethodInvocationException
+ FullyQualifiedErrorId : ConfigurationErrorsException"

Any help solving this?

Conexão MySQL Server 8.0 com MySQL Connector Net 6.8.3 (1 reply)

Pedro Muniz Muniz — Sat, 24 Feb 2024 17:08:26 +0000

Boa tarde, pessoal!
Sou novato em MySQL e estou tendo dificuldades de efetuar a conexão do Visual Studio VB.net com o servidor MySQL.
Pelo VS ser de 2013, só consigo utilizar o MySQL Connector 6.8.3.
Instalei o MySQL Server 8.0.
MInha pergunta é: Posso efetuar a conexão ao MySQL Server 8.0 com o Connector 6.8.3?
Se é possível, por favor me digam como, pois já tentei de várias formas e nada funciona.
Muito obrigado!

Transaction issues using connector 8.x on a Server 5.7.x (no replies)

Sergio Sergio — Thu, 22 Feb 2024 17:39:11 +0000

I hope you can help me. I have a vb.Net system running stable on MySql RDS 5.7 for a few years. Due to the EOL of 5.7, we prepared the migration to MySql 8, and it is practically ready and fully tested. But to minimize the migration process, we updated the project that used the 6.9.x connector (Mysql.Data.dll) to the 8.3.0 connector, which is backwards compatible with MySql 5.7. However, we are facing a strange problem: with new connector, pointing to MySql 5.7, the behavior of transactions is different. With the new connector, transactions are getting stuck and not finishing correctly, generating a cascade effect that crashes the entire instance. If I return the connector to 6.9.x the problem disappears. Since the DB instance is exactly the same, I can't figure out how simply changing the connector could cause different behavior with transactions. Some important information: some transactions may be causing problems even with the old connector, but simply changing the connector should not justify such different behavior. I've tried several versions within 8.x (from version 8.0 to version 8.3) and it seems that they all have this problem. I use the .net 4.6.2 framework.

Thank you and I hope you can help me!

i'm expecting same behavior using any .net MySql Connector and I'm afraid of this problems occurs in MySql Server 8.0.35.

MySQL 8.3 Nuget Assemblies (1 reply)

Tim Babcock — Thu, 15 Feb 2024 15:54:25 +0000

After updating from MySQL 8.2 to 8.3, I updated the MySql.Data, MySql.Data.EntityFramework, and MySql.Web to 8.3.

Using the MySqlSessionStateStore.cs, an error appeared in the following section:

Unable to cast object of type 'System.Byte[]' to type 'System.String' under the following line of code:

Line 417: serializedItems = reader.GetString(1);

This error went away when 8.2 drivers were reloaded. No coding was changed on the app.

The code is used to change the MySqlSesssionStateStore since autocommit is turned off on the server.

The full code is found on kimple.com.

// Retrieve session item data from the data source.
reader = cmd.ExecuteReader(CommandBehavior.SingleRow);
while (reader.Read())
{
expires = reader.GetDateTime(0);

if (expires < DateTime.Now)
{
// The record was expired. Mark it as not locked.
locked = false;
// The session was expired. Mark the data for deletion.
deleteData = true;
}
else
foundRecord = true;

serializedItems = reader.GetString(1);
lockId = reader.GetInt32(2);
lockAge = DateTime.Now.Subtract(reader.GetDateTime(3));
actionFlags = (SessionStateActions)reader.GetInt32(4);
timeout = reader.GetInt32(5);
}
reader.Close();

Connector/NET for PowerBI (2 replies)

Nicholas Olmedo — Thu, 03 Oct 2024 05:35:00 +0000

Hello ~
I am pretty new to using MySQL and recently downloaded MS PowerBI. I want to connect a MySQL Database to PowerBI so I can easily import the data. PowerBI gave me a error message saying I must download the Connector/NET 8.3.0 in order to connect to MySQL.
After downloading, I am still unable to connect to MySQL database and receive the same error message. I'm wondering if anyone else has ran into this problem.

Unable to Connect PowerBi Desktop to MySql installed on Raspbery PI (1 reply)

MUSTAFA OEZTUERK — Tue, 20 Feb 2024 14:20:58 +0000

Hi Community,

I am trying to connect PowerBi Desktop (on Windows laptop) to MySql which is installed on my Raspberry PI but it just does not work. I always get the following error message:

Details: "An error happened while reading data from the provider: 'Object cannot be cast from DBNull to other types.'"

MySQL Version: Ver 15.1 Distrib 10.11.4-MariaDB, for debian-linux-gnu (aarch64)
MySQL Connector/net: Tried with 8.3.0, 8.0.27 and 8.0.28

Does anyone know how to resolve this issue. I did extensive search on the internet but simply cannot find the solution.

Any help is highly appriciated

Thanks

Mustafa

New problem with .Net connecttor v8.0.33.1 - System.Runtime.CompilerServices.Unsafe (3 replies)

Andrew Cutforth — Thu, 18 Jan 2024 17:57:47 +0000

I am using C# .NET Framework 4.8.1

I was using MySql .Net connector v8.0.32 just fine.

I upgraded to connector v8.0.33.1 which compiles but at runtime when accessing the database I get the following error:
Could not load file or assembly 'System.Runtime.CompilerServices.Unsafe, Version=4.0.4.1, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified

I have no idea how to fix this so I have gone back to v8.0.32.

Any ideas what is wrong?

Connection string special characters (no replies)

Sven Jupp — Tue, 02 Jan 2024 18:19:55 +0000

I have a visual studio Windows form programme that I connect to a MySQL database. I recently updated the server and now it wants special characters in the password. The problem I have is when the connection string is passed to the database the special characters through an error. I have connected to the database via and ODBC connection in excel, so I know my connection string works its just when Visual Studio 2019 sends it to the server that something goes wrong. I have no idea how to solve this one. I am using the latest MySQL.data.dll. The password has a * character in it. I have tried other characters with no success.

I writing my programme in vb, but I have tried the connection string builder to no effect. I am using vsto 2019. I have updated the mysql.data.dll to the latest (8.2.0.0). The database is MariaDB 10. The project is a Windows Forms Application with .NET framework 4.8.

When I pass the connection string with a special character in the password I get the following error message: 'Object cannot be cast from DBNull to other types.'.

When I pass the connection string with the special character removed (as a test really) I get the following error message: 'Authentication to host 'xx.x.xxx.xx' for user 'SDJ' using method 'mysql_native_password' failed with message: Access denied for user 'SDJ'@'xx.x.xxx.xx' (using password: YES)'

I can connect to the database using an ODBC connection via excel, so its something to do with how vsto is passing the password during connection.

Upgrade Application from MySQL .net connector from v8.0.27 to 8.0.33 | Required system restart to detect connector in Application (no replies)

Anshul Gupta — Wed, 13 Dec 2023 15:08:52 +0000

Hi All,

I upgraded .net mysql connector from v8.0.27 to v8.0.33 in my application but after upgrading it My Application is not detecting the connector is installed in the system untill I am restarting the system. This behavior was not there with .net MySQL connector v8.0.27, Below is the different behavior in v8.0.33

Scenario - 1(When I was using .net MySQL connector v 8.0.27) :-
1. Install My Application
2. Install MySQL connector v8.0.27
3. My Application can connect with MySQL database.

Scenario - 2(After Upgrading .net MySQL connector v8.0.33) :-
1. Install My Application
2. Install MySQL connector v8.0.33
3. My Application is not able to connect with MySQL database
4. Restart the system
5. My Application can connect with MySQL database.

so why the system restart is required for .net MySQL connector v8.0.33?

Install of ADO.NET Connector 8.2 only works with IPv4 (no replies)

Stephen Henderson — Thu, 30 Nov 2023 11:32:17 +0000

We have just updated the MySQL ASO.NET Connector on our Windows Servers to 8.2.0 to match the MySQL servers which have been upgraded to MySQL8. We are using the connector from within Microsoft SSIS jobs and found that it tried to access the MySQL database over IPv4 even though the both the Windows server and the server running the MySQL database had IPv6 IP addresses. Doing a simple ping to the same URL showed the IPv6 IP address. The ODBC connections to the same MySQL server worked flawlessly.
The workaround we figured out was to force the IPv6 IP address on the server by placing the URL and IPv6 IP address in the local machine's Hosts file.
Is there a known issue with the ADO.NET connector wanting to use IPv4 instead of IPv6? Are there any parameters which we can use to force IPv6 to be used each time. We currently have static DNS entries pointing to IPv6 IP addresses and if the admins ever changed the IP address of the MySQL database this would stop working until we matched this in the Hosts file.