connection must be valid and open 错误在visual studio中 [英]Connection must be valid and open error in visual studio
MySql Visual Studio 2017(错误:您已经有一个可用的连接) [英]MySql Visual Studio 2017 (Error: You have a usable connection already)
无法将 MySQL 服务器连接到 Visual Studio; 连接错误 40 [英]Cannot connect MySQL server to visual studio; Connection Error 40