Question

/ *格式化于2015/06/24 15:51（Formatter Plus v4.8.5）* /

SELECT   (SELECT NAME
            FROM dept
           WHERE deptid = department) AS NAME, SUM (received),
         SUM (notresponded)
    FROM (SELECT     TRIM (regexp_substr (b.dept, '[^,]+', 1, LEVEL)
                          ) AS department,
                     COUNT (*) received,
                       COUNT (*)
                     - COUNT
                          (CASE
                              WHEN ROUND
                                     (  (  TO_DATE
                                               (TO_CHAR (clssndtm,
                                                         'YYYY-MM-DD hh24:mi'
                                                        ),
                                                'YYYY-MM-DD hh24:mi'
                                               )
                                         - TO_DATE
                                               (TO_CHAR (made,
                                                         'YYYY-MM-DD hh24:mi'
                                                        ),
                                                'YYYY-MM-DD hh24:mi'
                                               )
                                        )
                                      * 24
                                     ) <= 1
                                 THEN ROUND
                                        (  (  TO_DATE
                                                 (TO_CHAR
                                                         (clssndtm,
                                                          'YYYY-MM-DD hh24:mi'
                                                         ),
                                                  'YYYY-MM-DD hh24:mi'
                                                 )
                                            - TO_DATE
                                                 (TO_CHAR
                                                         (made,
                                                          'YYYY-MM-DD hh24:mi'
                                                         ),
                                                  'YYYY-MM-DD hh24:mi'
                                                 )
                                           )
                                         * 24
                                        )
                              ELSE NULL
                           END
                          ) notresponded
                FROM reportng a, routing b
               WHERE a.ticket = b.ticket
                 AND (1 = 1)
                 AND a.rptflag = 1
                 AND a.clssndtm IS NOT NULL
                 AND companyid = 2682
          CONNECT BY INSTR (dept, ',', 1, LEVEL - 1) > 0
                 AND TRUNC (made) BETWEEN TRUNC (TO_DATE ('06/01/2015',
                                                          'mm/dd/yyyy'
                                                         )
                                                )
                                      AND TRUNC (TO_DATE ('06/23/2015',
                                                          'mm/dd/yyyy'
                                                         )
                                                )
            GROUP BY TRIM (regexp_substr (dept, '[^,]+', 1, LEVEL)))
GROUP BY department

Answer 1

首先，您希望查询可读，否则无法查看正在进行的操作：

SELECT
    (SELECT NAME FROM dept WHERE deptid = department) AS NAME,
    SUM (received),
    SUM (notresponded)
FROM
    (SELECT
        TRIM (regexp_substr (b.dept, '[^,]+', 1, LEVEL) ) AS department,
        COUNT () received,
        COUNT () - COUNT (CASE WHEN ROUND ( ( TO_DATE (TO_CHAR (clssndtm, 'YYYY-MM-DD hh24:mi' ), 'YYYY-MM-DD hh24:mi' ) - TO_DATE (TO_CHAR (made, 'YYYY-MM-DD hh24:mi' ), 'YYYY-MM-DD hh24:mi' ) ) * 24 ) <= 1 THEN ROUND ( ( TO_DATE (TO_CHAR (clssndtm, 'YYYY-MM-DD hh24:mi' ), 'YYYY-MM-DD hh24:mi' ) - TO_DATE (TO_CHAR (made, 'YYYY-MM-DD hh24:mi' ), 'YYYY-MM-DD hh24:mi' ) ) * 24 ) ELSE NULL END ) notresponded
    FROM
        reportng a,
        routing b
    WHERE
        a.ticket = b.ticket
        AND (1 = 1)
        AND a.rptflag = 1
        AND a.clssndtm IS NOT NULL
        AND companyid = 2682
        CONNECT BY INSTR (dept, ',', 1, LEVEL - 1) > 0 AND TRUNC (made) BETWEEN TRUNC (TO_DATE ('06/01/2015', 'mm/dd/yyyy' ) ) AND TRUNC (TO_DATE ('06/23/2015', 'mm/dd/yyyy' ) )
    GROUP BY
        TRIM (regexp_substr (dept, '[^,]+', 1, LEVEL))
    )
GROUP BY
    department

现在，那里有一些Oracle特定的东西，我不明白，但我们可以看到这里有两个不同的主要步骤。有第一个内部查询，可能有效也可能无法有效运行。单独运行它以查看它是如何进行的。我会认为它很好（可能不是）。

由于SELECT子句中有相关查询，因此外部位肯定不是最理想的。这需要分成一个连接：

SELECT
    dept.NAME,
    SUM (received),
    SUM (notresponded)
FROM
    complex_inner_query
    inner join dept on dept.deptid = complex_inner_query.department
GROUP BY
    department

这可能很好地解决您的问题，但如果不是，您需要开始分析内部查询以找出效率低下。

如何快速运行sql查询以下查询继续运行建议我如何优化它

1 个答案: