我正在处理MySQL数据库。我有一个表empreporting，这个表包含employeeid和reportingemployeeid列SELECTe3.`ReportingEmployeeId`ASLevel0,e2.`ReportingEmployeeId`ASLevel1,e1.`ReportingEmployeeId`ASLevel2,e1.`EmployeeId`ASLevel3FROMempreportinge1LEFTJOINempreportinge2ONe1.`ReportingEmployeeId`=e2.`EmployeeId`LEFTJOINempreporti