Question

我的mysql查询

SELECT  count(ICD10) as columnDis, ICD10
FROM(
     SELECT tbl_disease.ICD10, tbl_symptom_disease.symptomCode 
     FROM `tbl_disease`
     JOIN tbl_symptom_disease
     ON tbl_disease.ICD10=tbl_symptom_disease.diseaseCode
     WHERE tbl_symptom_disease.symptomCode='P18' 
     OR tbl_symptom_disease.symptomCode='P19'
    ) AS tbl_ICD10_symCode
GROUP BY ICD10
HAVING columnDis=?????

因此，此查询将返回所有具有重复值等于?????的ICD10条目。

在这个例子中，重复的最大数量是2，但我想将它用于不同的sympomCode（s），在这种情况下，可能有3个重复的条目出现5次，5个其他的出现3次，1个出现2次，依此类推。所以我需要的只是出现MOST次数的重复条目。类似的东西：

HAVING columnDis=(MAX(columnDis))

但那当然不起作用。有人可以帮帮我吗？

Answer 1

使用子查询获取最大计数，然后将其与主要子查询

连接

SELECT ICD10
FROM
(
    SELECT MAX(disease_count) AS max_disease_count
    FROM
    (
        SELECT tbl_disease.ICD10, COUNT(tbl_disease.ICD10) AS disease_count
        FROM `tbl_disease`
        JOIN tbl_symptom_disease
        ON tbl_disease.ICD10=tbl_symptom_disease.diseaseCode
        WHERE tbl_symptom_disease.symptomCode='P18' 
        OR tbl_symptom_disease.symptomCode='P19'
        GROUP BY ICD10
    ) sub0
) sub1
INNER JOIN
(
    SELECT tbl_disease.ICD10, COUNT(tbl_disease.ICD10) AS disease_count
    FROM `tbl_disease`
    JOIN tbl_symptom_disease
    ON tbl_disease.ICD10=tbl_symptom_disease.diseaseCode
    WHERE tbl_symptom_disease.symptomCode='P18' 
    OR tbl_symptom_disease.symptomCode='P19'
    GROUP BY ICD10
) sub2
ON sub1.max_disease_count = disease_count

Mysql需要选择具有最大数量的多个条目的所有值

1 个答案: