我有一个这样的表:+------+-----------+|caseID|groupVarian|+------+-----------+|1|A,B,C,D,E|+------+-----------+|2|A,B,N,O,P|+------+-----------+|3|A,B,N,O,P|+------+-----------+|4|A,B,C,D,F|+------+-----------+|5|A,B,C,D,E|+------+-----------+我想获得一个新列nameVarian，这样相同的groupVarian值具有由nameVarian表示的相同排名(例如:v1