mysql怎么查询序号中未出现的数据

1002
2024/5/12 10:14:08
栏目: 云计算
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可以使用以下SQL语句来查询序号中未出现的数据:

SELECT missing_numbers.number
FROM (
    SELECT ones.number + tens.number * 10 + hundreds.number * 100 AS number
    FROM (SELECT 0 AS number UNION SELECT 1 UNION SELECT 2 UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6 UNION SELECT 7 UNION SELECT 8 UNION SELECT 9) AS ones
    CROSS JOIN (SELECT 0 AS number UNION SELECT 1 UNION SELECT 2 UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6 UNION SELECT 7 UNION SELECT 8 UNION SELECT 9) AS tens
    CROSS JOIN (SELECT 0 AS number UNION SELECT 1 UNION SELECT 2 UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6 UNION SELECT 7 UNION SELECT 8 UNION SELECT 9) AS hundreds
) AS missing_numbers
LEFT JOIN your_table ON missing_numbers.number = your_table.id
WHERE your_table.id IS NULL
ORDER BY missing_numbers.number;

在这个SQL语句中,我们首先生成一个包含所有可能序号的临时表missing_numbers,然后左连接your_table表,通过判断your_table.id是否为NULL来确定序号中是否未出现的数据。最后按照序号进行排序输出。

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