带有WHERE的DISTINCT子句

Question

如何在WHERE中使用DISTINCT子句？例如：

SELECT * FROM table WHERE DISTINCT email; -- email is a column name

我想从具有不同电子邮件地址的表中选择所有列。

Answer 1

如果您指的是其电子邮件唯一的所有列：

SELECT * FROM table WHERE email in
     (SELECT email FROM table GROUP BY email HAVING COUNT(email)=1);

Answer 2

尝试：

SELECT * FROM table GROUP BY email

• 这将返回所有行，其中包含第一个ID外观所采用的唯一电子邮件（如果这有意义）
• 我认为这是你所看到的，因为我有同样的问题，但这些答案都不适合我。

Answer 3

SELECT DISTINCT dbo.Table.Email，dbo.Table.FirstName dbo.Table.LastName，dbo.Table.DateOfBirth（etc）FROM dbo.Table.Contacts WHERE Email ='name @ email';

Answer 4

查询：

Select *, (Select distinct email) from Table1

Answer 5

select t1.*
from YourTable as t1
  inner join
    (select email
     from YourTable
     group by email
     having count(email) = 1 ) as t2
    on t1.email = t2.email   

Answer 6

可能是：

SELECT DISTINCT email,id FROM table where id='2';

Answer 7

您可以使用HAVING子句。

SELECT * 
FROM tab_name
GROUP BY email_id
HAVING COUNT(*) = 1;

Answer 8

您可以使用ROW_NUMBER（）。您也可以指定条件。 （例如，在以下查询中的Name LIKE'MyName%）

SELECT  *
FROM    (SELECT ID, Name, Email,
            ROW_NUMBER() OVER (PARTITION BY Email ORDER BY ID) AS RowNumber
     FROM   MyTable
     WHERE  Name LIKE 'MyName%') AS a
WHERE   a.RowNumber = 1

Answer 9

一个简单的查询就可以了：

SELECT * 
FROM table 
GROUP BY email 
HAVING COUNT(*) = 1;

Answer 10

这不会起作用：

 SELECT email FROM table1 t1 
          where UNIQUE(SELECT * FROM table1 t2); 

Answer 11

简单查询此查询选择电子邮件唯一的表中的所有记录：

select distinct email,* from table_name

Answer 12

如果表中有一个唯一的列（例如tableid），那么试试这个。

SELECT EMAIL FROM TABLE WHERE TABLEID IN 
(SELECT MAX(TABLEID), EMAIL FROM TABLE GROUP BY EMAIL)