how i can test the connection with mysql?
lazarus / 16-Databases

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saul_linux · 2014-09-03 04:54

I am do a litle app, i need check if the server of mysql is down, but
i don't know.
I am using the MySQL55Connection  componet
i tried
Code: [Select]   try
     MySQL55Connection1.Open;

   finally
     if MySQL55Connection1.Connected=false then
     begin
        ShowMessage('connection fail');

     end;
   end;     


but when mysql is down, my app doesn't anything

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dogriz · 2014-09-03 05:43

Try like this:
Code: [Select]   try
     MySQL55Connection1.Open;
     if MySQL55Connection1.Connected=false then
        ShowMessage('connection fail');
   except
      //code for exception if you need it
   end;

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taazz · 2014-09-03 05:48

in order to test if the sql server is present the only thing you need
to have a simple tcp connection with the server succeed
mysqlConnection does a lot more than opening a connection to the
server it also initializes the server and client connection parameters
and transactions.
forget about testing with the MySQLConnection use a simple tcp client
to connect to the server's ip and port make sure that the time out
interval is small enough to avoid user waiting and big enough to allow
the connection to take place before the time out.