选择单个记录只

Question

我有一个表，这样

custno, type, color 
A1234, B, Red 
A1234, C, Blue 
A1277, B, Red 
A1288, A, Black 
A1288, B, Red 
A1289, A, Black 

我只需要获取唯一的记录A1277和A1289这只是一旦发现。

Answer 1

这将显示在结果列表中的custNO，

SELECT custNo 
FROM tableName 
GROUP BY custNO 
HAVING COUNT(*) = 1 

，但如果你想获得全排，

SELECT a.* 
FROM tableName a 
     INNER JOIN 
     (
      SELECT custNo 
      FROM tableName 
      GROUP BY custNO 
      HAVING COUNT(*) = 1 
     ) b ON a.custNo = b.custNo 

• SQLFiddle Demo (both queries)

Answer 2

SELECT custno 
FROM yourTable 
GROUP BY custno 
HAVING COUNT(*) = 1 

Example Fiddle

Answer 3

试试这个，因为这将避免代价高昂的加盟operation--

SELECT custno,type,color FROM ( SELECT custno, type, color, COUNT(custno) OVER(PARTITION BY custno) CNT FROM tableName )TMP WHERE CNT=1