How to resolve a database connection failure detected by Delphi?

1 year ago
Benjamin Taylor
1 minute

In Delphi, detecting a database connection failure can be handled by capturing exceptions. One common method is to use a try..except block to catch the database connection exception, and then reconnect to the database in the except block. Example code is shown below:

uses
  DB, DBXCommon, DBXError;

var
  conn: TSQLConnection;

begin
  conn := TSQLConnection.Create(nil);
  try
    conn.DriverName := 'MySQL';
    conn.Params.Add('HostName=127.0.0.1');
    conn.Params.Add('Database=mydatabase');
    conn.Params.Add('User_Name=myuser');
    conn.Params.Add('Password=mypassword');

    try
      conn.Open;
      // 连接成功
    except
      on E: TDBXError do
      begin
        // 数据库连接异常
        // 重新连接数据库
        conn.Close;
        conn.Open;
      end;
    end;
  finally
    conn.Free;
  end;
end;

In the provided code, we instantiate a TSQLConnection object and define connection parameters. We then attempt to open the database connection within a try block. If the connection fails, we catch the TDBXError exception in the except block, close the connection, and try to reconnect to the database.

It is important to note that in practical applications, we can also handle situations where database connections fail according to specific business logic and needs, such as logging and notifying the user.

bannerAds