Question

SELECT FirstName, LastName, MobileNo, COUNT(1) as CNT
FROM CUSTOMER
GROUP BY FirstName, LastName, MobileNo;

类似的事情将基于Customer，FirstName和LastName产生表MobileNo的重复。但是，我想基于所有列（未知）产生一个重复列表。我该怎么办？

Answer 1

您可以使用校验和（*）

sqlfiddle.com /＃！18 / 0a33d / 4

例如。

CREATE TABLE TEST_DATA
  ( Field1 VARCHAR(10),
    Field2 VARCHAR(10)
  );

INSERT INTO TEST_DATA VALUES ('1','1');
INSERT INTO TEST_DATA VALUES ('1','1');
INSERT INTO TEST_DATA VALUES ('2','2');
INSERT INTO TEST_DATA VALUES ('2','2');
INSERT INTO TEST_DATA VALUES ('2','2');
INSERT INTO TEST_DATA VALUES ('3','3');

SELECT TD1_CS.*
  FROM (SELECT TD1.*,
               CHECKSUM(*) CS1
          FROM TEST_DATA TD1
        ) TD1_CS
 INNER
  JOIN (SELECT CHECKSUM(*) CS2
          FROM TEST_DATA TD2
         GROUP 
            BY CHECKSUM(*)
        HAVING COUNT(*) > 1
       ) TD2_CS
    ON TD1_CS.CS1 = TD2_CS.CS2

Answer 2

SELECT  FirstName, LastName, MobileNo, COUNT(*)
FROM    CUSTOMER
GROUP BY FirstName, LastName, MobileNo
HAVING    COUNT(*) > 1

SQL基于所有列复制

2 个答案: