选择MySQL中的前十行

我的表格gainfinal由countrycode、year和values三列组成。我要选择具有前十个值的十行。首先，我使用以下查询根据值创建了一个排名

    SELECT countrycode, `values`,
    @curRank := @curRank + 1 AS rank
    FROM gainfinal CROSS JOIN
    (SELECT @curRank := 0) vars
    WHERE year = 2000
    ORDER By `values` DESC ;

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现在，我需要选择排名最高的前十行。我怎么做

您可以使用：Limit从第20行开始获得10行

    SELECT countrycode, `values`,
    @curRank := @curRank + 1 AS rank
    FROM gainfinal CROSS JOIN
    (SELECT @curRank := 0) vars
    WHERE year = 2000
    ORDER By `values` DESC ;

SELECT countrycode, `values`,
@curRank := @curRank + 1 AS rank
FROM gainfinal CROSS JOIN
(SELECT @curRank := 0) vars
WHERE year = 2000
ORDER By `values` DESC
LIMIT 10;

LIMIT 10 OFFSET 20 --Equivalent to LIMIT 20, 10

使用

    SELECT countrycode, `values`,
    @curRank := @curRank + 1 AS rank
    FROM gainfinal CROSS JOIN
    (SELECT @curRank := 0) vars
    WHERE year = 2000
    ORDER By `values` DESC ;

在SQL so示例中：

    SELECT countrycode, `values`,
    @curRank := @curRank + 1 AS rank
    FROM gainfinal CROSS JOIN
    (SELECT @curRank := 0) vars
    WHERE year = 2000
    ORDER By `values` DESC ;

SELECT countrycode, `values`,
@curRank := @curRank + 1 AS rank
FROM gainfinal CROSS JOIN
(SELECT @curRank := 0) vars
WHERE year = 2000
ORDER By `values` DESC
LIMIT 10

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还可以在where语句中使用秩变量

    SELECT countrycode, `values`,
    @curRank := @curRank + 1 AS rank
    FROM gainfinal CROSS JOIN
    (SELECT @curRank := 0) vars
    WHERE year = 2000
    ORDER By `values` DESC ;

...WHERE year = 2000 and @curRank <11;

---

…其中year=2000和@curRank在查询中添加
限制10
。