如果只有一个条目，请选择名称

Question

如果表中只有一个条目，我想在SQL中选择一个名称。 就像是

SELECT name
FROM stats
WHERE name =
  ( SELECT DISTINCT(name) FROM stats WHERE COUNT(name) < 1
  )

我知道这行不通，但是我怎么能得到呢？

Answer 1

使用HAVING

SELECT `name` 
FROM `stats` 
WHERE `name` = (
    SELECT DISTINCT(`name`) 
    FROM `playerstats` 
    HAVING COUNT(`name`) = 1
)

如果从一个表中选择，则不需要嵌套查询：

SELECT `name`
FROM `stats`
HAVING COUNT(`name`) = 1

Answer 2

这样的事情怎么样？

SELECT A.name 
FROM stats A
inner join (
SELECT count(*) `cnt`, name 
FROM stats 
group by name
) B on (A.name = B.name)
WHERE B.cnt = 1

Answer 3

我有机会！

SELECT name FROM stats WHERE name in（选择s2.name FROM stats s2 GROUP BY s2.name HAVING COUNT（*）= 1）;