[Lazarus] MariaDB gone away after long inactivities

[Eric Kom]

Hi Folks,
I got two procedures that are connected to MariaDB 5.6,
My goal is if my application was launch for a long time, it must not 
lost the connection with my database and if the connection to the 
database was lost due to any reasons and restored (MariaDB running 
again), the procedure must still connect to the database without the 
application been restarted.

I have initialized the connection to the database using TSQLConnection 
to avoided the client library to trough away the connection, PLEASE see 
below.

procedure TdataModuleMySQL.createConnection;
begin
   SQLConnection1 := TMySQL55Connection.Create(nil);
   SQLConnection1.HostName:='127.0.0.1';
   SQLConnection1.DatabaseName:='first';
   SQLConnection1.UserName:='erickom';
   SQLConnection1.Password:='tux.';
end;
procedure TdataModuleMySQL.startDatabase;
begin
    //Start of connection
    createConnection;
    //Open the connection & transaction
    SQLConnection1.Connected:=True;
    SQLConnection1.Transaction:=SQLTransaction1;
    SQLTransaction1.DataBase:=SQLConnection1;
end;

I use the first procedure to INSERT data in the database via 
TLabeledEdit component and  has been tested successfully , see below:

procedure TfrmMySQLTest.bitBtnInsertClick(Sender: TObject);
begin
try
   dataModuleMySQL.startDatabase;
   //Start of execution statment
   dataModuleMySQL.queryAtInsert;
   dataModuleMySQL.SQLQuery1.SQL.Text:='INSERT INTO student (names, dob) 
VALUES (:getNAMES, :getDOB);';
dataModuleMySQL.SQLQuery1.Params.ParamByName('getNAMES').AsString:=lblEdtNames1.Text;
dataModuleMySQL.SQLQuery1.Params.ParamByName('getDOB').AsString:=lblEdtDOB1.Text;
   //This lets you know via the label if you are connected or not.
   if dataModuleMySQL.SQLConnection1.Connected then
   begin
     lblStatus1.Caption:='Connected';
     try
        //This starts the query which was created in the connection string
        dataModuleMySQL.SQLQuery1.ExecSQL;
        //Close the database
        dataModuleMySQL.stopDatabase;
     except
       showMessage('Execution of your query with error; APP can not 
continued. ');
     end;
   end;
except
   lblStatus1.Caption:='Not Connected';
   showMessage('Database Connection Error. The database may be shutdown 
or network issue.');
end;

The second procedure is used to SELECT and display in the TDBGrid 
(Successfully done) but lost the connect  after the database been 
shutdown or when the application been running for long without 
activities, see below:

procedure TdataModuleMySQL.queryGrid;
begin
    SQLQueryGrid.DataBase:=SQLConnection1;
    SQLQueryGrid.Transaction:=SQLTransactionGrid;
    DataSource1.DataSet:=SQLQueryGrid;
    SQLQueryGrid.SQL.Text:='SELECT * FROM student;';
end;

procedure TfrmMySQLTest.btnGridClick(Sender: TObject);
begin
try
   dataModuleMySQL.startDatabase;
   //Start of execution statment
   dataModuleMySQL.queryGrid;

   DBGrid2.DataSource:=dataModuleMySQL.DataSource1;

   //This lets you know via the label if you are connected or not.

   if dataModuleMySQL.SQLConnection1.Connected then
   begin
           lblStatus3.Caption:='Connected';
                //This will also pass the inormation through to the GRID
                //This starts the query which was created in the 
connection string
           try
              dataModuleMySQL.SQLQueryGrid.Open;
           except
              showMessage('Execution of your query with error; APP can 
not continued.');
           end;
   end;
except
       lblStatus3.Caption:='Not Connected..';
       showMessage('Database Connection Error. The database may be 
shutdown or network issue.');
       dataModuleMySQL.createConnection;
end;
end;

I don't know if the datasource can be the problem or not? or it is a 
normal behave?

Thank you in advance