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Mysql随机获取,但尝试使用最小值获取_Mysql_Sql - Fatal编程技术网

Mysql随机获取,但尝试使用最小值获取

Mysql随机获取,但尝试使用最小值获取,mysql,sql,Mysql,Sql,我在MySQL表中有一行名为number\u of_times,我将此查询发送到SQLSELECT*FROM Vocab ORDER BY Rand()LIMIT 3,它返回3个随机数据,我如何选择3个随机数,但是从number\u of_times行最小的数据中,您需要选择最小的值。只需使用number of\u times作为order by中的第一个键: SELECT * FROM Vocab ORDER BY number_of_times asc, Rand() LIMIT 3; 注

我在MySQL表中有一行名为
number\u of_times
,我将此查询发送到SQL
SELECT*FROM Vocab ORDER BY Rand()LIMIT 3
,它返回3个随机数据,我如何选择3个随机数,但是从
number\u of_times
行最小的数据中,您需要选择最小的值。只需使用
number of\u times
作为
order by
中的第一个键:

SELECT *
FROM Vocab
ORDER BY number_of_times asc, Rand()
LIMIT 3;
注意:如果您只想要具有最小的
次数的值(即使没有3个),那么这可能会更快:

SELECT *
FROM Vocab
WHERE number_of_times = (SELECT MIN(number_of_times) from Vocab)
ORDER BY Rand()
LIMIT 3;
这可以利用
Vocab(次数)
上的索引