Question

我正在进行查询以计算不同类别的不同类别的条目数。我先按类别对表格的行进行分组，然后按州进行分组。这是我当前查询的一个版本：

SELECT
    CASE
    WHEN J.MISC_CATEGORY_CONFIG IN (
            'A_1',
            'A_2'
        ) THEN 'Category A'
    WHEN J.MISC_CATEGORY_CONFIG IN (
            'B_1',
            'B_2'
        ) THEN 'Category B'
    WHEN J.MISC_CATEGORY_CONFIG IN (
            'C_1',
            'C_2'
        ) THEN 'Category C'
    ELSE 'Other'/*This should not happen, if it does, something is wrong.*/
    END AS CATEGORY,
    J.STATUS,
    COUNT(*) AS STATUS_COUNT
FROM JOB J
WHERE J.FINISHED_TIME > DATE_SUB(CURDATE(), INTERVAL 7 DAY)
AND (
    DAYNAME(J.FINISHED_TIME) = 'Saturday'
    OR DAYNAME(J.FINISHED_TIME) = 'Sunday')
AND J.MISC_CATEGORY_CONFIG IN (
    /*All relevant categories*/
   'A_1',
   'A_2',
   'B_1',
   'B_2',
   'C_1',
   'C_2'
)
GROUP BY
    CASE
    WHEN J.MISC_CATEGORY_CONFIG IN (
            'A_1',
            'A_2'
        ) THEN 'Category A'
    WHEN J.MISC_CATEGORY_CONFIG IN (
            'B_1',
            'B_2'
        ) THEN 'Category B'
    WHEN J.MISC_CATEGORY_CONFIG IN (
            'C_1',
            'C_2'
        ) THEN 'Category C'
    ELSE 'Other'/*This should not happen, if it does, something is wrong.*/
    END,
    J.STATUS

查询结果目前如下所示：

CATEGORY   | STATUS   | COUNT

Category A   Success    117

Category A   Failure    19

Category B   Success    208

当我需要结果如下：

CATEGORY   | STATUS   | COUNT

Category A   Success    117

Category A   Failure    19

Category B   Success    208

Category B   Failure    0

Category C   Success    0

Category C   Failure    0

如何修改我的查询以便以这种方式返回空行，这样如果没有行，所有类别都会在结果集中以0显示？

Answer 1

或许这样的事情：
我们创建了一组包含我们关心的相关类别/状态的数据（我称之为AllCatStat），我们将其加入到作业中的基本数据集中，这样我们就可以分组并获取左侧相关状态记录的计数加入表。这将是0记录到x记录。

SELECT AllCatStat.Category
     , AllCatStat.Status
     , count(J.Status) as COUNT
/*Get Distinct category and status for all jobs having a misc_Category_Config we care about*/

FROM (SELECT DISTINCT CASE WHEN J.MISC_CATEGORY_CONFIG IN ('A_1','A_2') THEN 'Category A'
                           WHEN J.MISC_CATEGORY_CONFIG IN ('B_1','B_2') THEN 'Category B'
                           WHEN J.MISC_CATEGORY_CONFIG IN ('C_1','C_2') THEN 'Category C' 
                           ELSE 'Other' End as Category,
                           J.Status
      FROM JOB
      WHERE MISC_CATEGORY_CONFIG IN ('A_1', 'A_2', 'B_1', 'B_2','C_1','C_2'))  AllCatStat

/*Get List of Jobs Meeting our criteria and format to desired category*/
LEFT JOIN (SELECT CASE WHEN J.MISC_CATEGORY_CONFIG IN ('A_1','A_2') THEN 'Category A'
                       WHEN J.MISC_CATEGORY_CONFIG IN ('B_1','B_2') THEN 'Category B'
                       WHEN J.MISC_CATEGORY_CONFIG IN ('C_1','C_2') THEN 'Category C'
                       ELSE 'Other' /*This should not happen, if it does, something is wrong.*/
                       END AS CATEGORY,
                  J.STATUS
           FROM JOB J
           WHERE J.FINISHED_TIME > DATE_SUB(CURDATE(), INTERVAL 7 DAY)
             AND (DAYNAME(J.FINISHED_TIME) = 'Saturday'
               OR DAYNAME(J.FINISHED_TIME) = 'Sunday')
             AND J.MISC_CATEGORY_CONFIG IN ('A_1',   'A_2',   'B_1',   'B_2',   'C_1',   'C_2')
          ) J
 ON AllCatStat.Category = J.Category
and AllCatStat.Status = J.Status

GROUP BY AllCatStat.CATEGORY
       , AllCatStat.STATUS

Mysql - 0如果没有行计数

1 个答案: