IF OBJECT_ID(‘cardDetail‘) IS NOT NULL DROP TABLE cardDetail CREATE TABLE cardDetail ( id INT IDENTITY(1,1) PRIMARY KEY, cardNO VARCHAR(8), NAME VARCHAR(30), idCard VARCHAR(18), cardState CHAR(1)--卡片状态 1正常 2注销 ) INSERT cardDetail(cardNO,NAME,idCard,cardState) VALUES (‘001‘,‘张三‘,‘31010‘,1), (‘005‘,‘张三‘,‘31010‘,1), (‘002‘,‘李四‘,‘31011‘,1), (‘003‘,‘王五‘,‘31012‘,1), (‘006‘,‘张三‘,‘31010‘,0), (‘004‘,‘王五‘,‘31012‘,1), (‘007‘,‘欧阳‘,‘31013‘,1), (‘008‘,‘欧阳‘,‘31013‘,1)
--SQL编写要求
--根据idcard,cardstate分组后删除重复的,使其保留id最小的记录
--最终结果为:
(1,‘001‘,‘张三‘,‘31010‘,1),
(4,‘003‘,‘王五‘,‘31012‘,1),
(7,‘007‘,‘欧阳‘,‘31013‘,1),
解决
with t as ( select id,cardNO,NAME,idCard,cardState, row_number() over (partition by idcard,cardstate order by id) as od from cardDetail ) select * from t where od = 1;