sql - 从表中选择随机行

Question

我想从 Admin_Pic_Lib 的整个表中选择 24 个随机行，但是这个查询给出了语法错误，

 SELECT top 24 CAST( [Pictures] AS varbinary(Max)) FROM Admin_Pic_Lib ORDER BY NEWID()

 UNION ALL 

  SELECT  CAST([Pictures] AS varbinary(Max))   FROM User_images  WHERE UserName ='ahmed'

当我修剪ORDER BY NEWID()它时，只选择前 24 行。

Answer 1

请尝试以下代码。

SELECT Pictures 
FROM 
    (SELECT TOP 24 CAST([Pictures] AS varbinary(Max)) AS Pictures 
     FROM Admin_Pic_Lib ORDER BY NEWID()) AS X

 UNION ALL 

  SELECT  CAST([Pictures] AS varbinary(Max)) AS Pictures 
  FROM User_images
  WHERE UserName ='ahmed'