How To connect to mysql database with EntityFramework Core?

Question

In the goal to use asp.net core mvc with the mysql database , i have downloaded the specific provider of EF_Core for Mysql.

Then i registred the DbContext service in the startup file:

 services.AddDbContext<NawrasContext>(options=>
               options.UseMySql(Configuration.GetConnectionString("DefaultConnection")));

and this is my appsettings.json :

  {
  "Logging": {
    "LogLevel": {
      "Default": "Warning"
    }
  },
  "AllowedHosts": "*",
  "ConnectionStrings": {
    "DefaultConnection": "Server=s.mysql.db;Database=s2019;Uid=s2019;Pwd=pass;"

  }
}

I have successfully added my first migration , but when i try to update the database , i get this error :

fail: Microsoft.EntityFrameworkCore.Database.Connection[20004]
  An error occurred using the connection to database '' on server 's.mysql.db'.
MySql.Data.MySqlClient.MySqlException (0x80004005): Unable to connect to any of the specified MySQL hosts.
 at MySqlConnector.Core.ServerSession.ConnectAsync(ConnectionSettings cs, ILoadBalancer loadBalancer, IOBehavior ioBehavior, CancellationToken cancellationToken) in C:\projects\mysqlconnector\src\MySqlConnector\Core\ServerSession.cs:line 440

what i m doing wrong ? why the error is telling me :

An error occurred using the connection to database '' on server 's.mysql.db'. while the name of the database in the connection string is specified ?

You should not include sensitive info in any question, Please replace your server, user and pass with any placeholder text for your own security — Muhammad Omar ElShourbagy, Aug 05 '20 at 15:02

score 2 · Answer 1 · edited Jun 16 '22 at 19:47

2

Using these steps you can solve the issue

Use a Nugat package named "Pomelo.EntityFrameworkCore.MySql"
Register service to Startup.cs

services.AddCors();

services.AddDbContext<NawrasContext>(options =>options.UseMySql(Configuration.GetConnectionString("DefaultConnection")));

Use this connection string in appsettings.json

{
  "Logging": {
    "IncludeScopes": false,
    "LogLevel": {
      "Default": "Warning"
    }
  },

  "ConnectionStrings": {
    "DefaultConnection": "Server=myServerAddress;Database=myDataBase;Uid=myUsername;Pwd=myPassword; Encrypt=true;"
  }
}

edited Jun 16 '22 at 19:47

Zarepheth

2,465
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answered Oct 25 '19 at 09:51

Abdullah Al Mamun Shiham

31
2

the server is online not localhost – A.HADDAD Oct 25 '19 at 10:50
Use connection sting like above [edited] and let me know if it works or not – Abdullah Al Mamun Shiham Oct 25 '19 at 16:17
Hello Abdullah, am facing the same issue and the above solution did not solve it. Kindly take a look at my question here: https://stackoverflow.com/q/61427947/12175082 – Russell Chidhakwa Apr 25 '20 at 19:30

score 0 · Answer 2 · answered Nov 06 '20 at 13:29

I had same issue using mac with MAMP as server for MySQL and the fix for me was to enable Allow network access to MySQL => Only from this Mac and then the server variable in connection string was like this :

"server=/Applications/MAMP/tmp/mysql/mysql.sock;port=8889;user=root;password=MyAwesomePassword;database=MyAwesomeDb;"

so basically try to put the mysql.sock path instead of localhost.

hope this will help someone , thanks .

How To connect to mysql database with EntityFramework Core?

2 Answers2