谁能帮我完成这个任务..
FirstName LastName EmpNumber EffectiveFrom EffectiveTo JobTitle
john A EMP01 2004-05-01 2005-09-01 credit officer
NULL NULL NULL 2005-09-01 2006-30-01 chief credit officer
NULL NULL NULL 2006-30-01 2006-30-09
george B EMP02
david C EMP03
NULL NULL NULL
NULL NULL NULL
我有这样的表,想用光标更新它看起来像这样我没有写所有数据只是一些记录
FirstName LastName EmpNumber EffectiveFrom EffectiveTo JobTitle
john A EMP01
john A EMP01
john A EMP01
george B EMP02
david C EMP03
david C EMP03
david C EMP03