C# Mysql with Fatal error

Question

The script works fine in the Workbench but when I use it in C# I get " Fatal error encountered during command execution. "

I can not see the error, but I believe it is by "@"

cmd.CommandText = "CREATE TABLE temp_update_table (matricula VARCHAR(50) NOT NULL, nome VARCHAR(150) NOT NULL, cargo VARCHAR(50) NOT NULL, nasc VARCHAR(50) NOT NULL, admissao VARCHAR(50) NOT NULL, cpf VARCHAR(50) NOT NULL, status VARCHAR(50) NOT NULL);";
cmd.ExecuteNonQuery();
cmd.CommandText = @"LOAD DATA LOCAL INFILE '//10.5.0.2/c$/dhcp.txt' INTO TABLE temp_update_table FIELDS TERMINATED BY ';' LINES TERMINATED BY '\n' IGNORE 1 LINES (@col1, @col2) set matricula = @col1, nome = @col2;"; 
cmd.ExecuteNonQuery();

When I do the script below, it works:

Cmd.CommandText = "LOAD DATA LOCAL INFILE '//10.5.0.2/c$/dhcp.txt' INTO TABLE temp_update_table FIELDS TERMINATED BY ';' LINES TERMINATED BY '\\n' IGNORE 1 LINES;";

But when I put the end it generates the error " Fatal error encountered during command execution. ":

... LINES (@col1, @col2) set matricula = @col2, name = @co1;";

Answer 1

I was building a .NET C# application with a MySQL database, and I too kept running into the error message:

"Fatal error encountered during command execution."

When calling the "LOAD DATA INFILE" MySQL command from my .NET application. It was very hard to figure out the solution, so I wanted to respond here with the solution that worked for me. Eventually, after several days of reading everything I could find about the problem (including this post), I was able to fix it...and the solution was not intuitive by any means, and it ended up being two different issues!

The first fix I found was that, when you're using variables in your INFILE, you need to add the following statement to your connection string (believe it or not):

"Allow User Variables=True;"

So, that means your complete connection string should look something like this:

"server=127.0.0.1;uid=user;pwd=password;database=mysql_db_name;Allow User Variables=True"

This surprised me, but seemed to work!! I found that solution here: MySQL fatal error encountered during command execution - looping through all csv files in folder for load data local infile

However, after I modified the connection string, although most input files started working for me, I was STILL getting this error message intermittently. I would get the error message "Fatal error encountered during command execution" for some input files and not others?? After reading more and playing around with things, it seemed to be a problem of the connection timing out (or something weird like that), even though the error message did NOT say anything about a connection timeout. I was able to stop the error message from popping up and correctly import data files into MySQL by increasing the "CommandTimeout" property on the database "MySqlCommand" object in C#, like this:

mysqlCommand.CommandTimeout = 600;

So, the full code looked something like this:

string strConnect = "server=127.0.0.1;uid=user;pwd=password;database=mysql_db_name;Allow User Variables=True";
Using (MySqlConnection mysqlConnection = new MySqlConnection(strConnect))
{
    Using (MySqlCommand mysqlCommand = new MySqlCommand())
    {
        mysqlCommand.CommandTimeout = 600;
        mysqlCommand.Connection = mysqlConnection;
        mysqlCommand.CommandType = CommandType.Text;

        mysqlCommand.CommandText = "LOAD DATA INFILE (...your specific command here)";

        try
        {
            mysqlConnection.Open();
            mysqlCommand.ExecuteNonQuery();
            mysqlConnection.Close();
        }
        catch(Exception ex)
        {
            // handle errors
        }
    }
}

And I found that particular solution after reading this post: Sourcing 'Fatal Error' resulting from MySQL ExecuteNonQuery?

Anyway, I think that was everything I needed to do to solve my problem. Hopefully this information is helpful for you too. Good luck and happy coding!