Question

如何将这两个查询合并为1？两者都使用2个不同的数据库，但都在同一台服务器上。我会在这里使用子选择或联合吗？

我基本上想要显示以下内容：

User name | Total A | Total B
jon           5          3
tim           4          2
sarah         3          1

以下是查询：

首先查询：

SELECT
  U.USR_USERNAME AS `User Name`,
  COUNT(rp_workflow.PIG.APP_UID) AS 'Total A'
FROM
  rp_workflow.PMT_INSP_GRID PIG
  JOIN
  rp_workflow.PMT_INSP_NORMAL PIN
  ON PIG.APP_UID = PIN.APP_UID
  JOIN
  wf_workflow.USERS U
  ON PIN.USR_UID_ORDER = U.USR_UID
GROUP BY
U.USR_USERNAME

第二次查询：

SELECT
  U.USR_USERNAME AS `User Name`,
  COUNT(rp_workflow.PIQG.APP_UID) AS 'Total B'
FROM
  rp_workflow.PMT_INSP_QC_GRID PIQG
  JOIN
  rp_workflow.PMT_INSP_NORMAL PIN
  ON PIQG.APP_UID = PIN.APP_UID
  JOIN
  wf_workflow.USERS U
  ON PIN.USR_UID_QC = U.USR_UID
  WHERE
  PIN.APP_STATUS = 'Completed'
 GROUP BY
 U.USR_USERNAME

编辑：尝试了一个子选择，但最终只显示了第二个查询的所有值的总和。感觉我很亲密，但也变得更加困惑。

SELECT
  U.USR_USERNAME AS `User Name`,
  COUNT(rp_workflow.PIG.APP_UID) AS 'Total A',
  (SELECT
    COUNT(rp_workflow.PIQG.APP_UID)
  FROM
      rp_workflow.PMT_INSP_QC_GRID PIQG
  JOIN
  rp_workflow.PMT_INSP_NORMAL PIN
  ON PIQG.APP_UID = PIN.APP_UID
  JOIN
  wf_workflow.USERS U
  ON PIN.USR_UID_QC = U.USR_UID
  WHERE
  PIN.APP_STATUS = 'Completed') AS 'Total B'
FROM
  rp_workflow.PMT_INSP_GRID PIG
  JOIN
  rp_workflow.PMT_INSP_NORMAL PIN
  ON PIG.APP_UID = PIN.APP_UID
  JOIN
  wf_workflow.USERS U
  ON PIN.USR_UID_ORDER = U.USR_UID
GROUP BY
U.USR_USERNAME

它显示的内容：

User name | Total A | Total B
jon           5          6

编辑2：*表PIG或PIQG中不存在USR_UID，因此必须将它们连接到表PIN。从那里，可以检索用户名

尝试了此查询，但最终收到了一个未知的列错误：

    SELECT wf_workflow.U.USR_USERNAME AS `User Name` ,

      (SELECT count(PIG.APP_UID)
       FROM rp_workflow.PMT_INSP_GRID PIG
       JOIN rp_workflow.PMT_INSP_NORMAL PIN ON PIG.APP_UID = PIN.APP_UID
       AND PIN.USR_UID_ORDER = U.USR_UID) AS 'Total A',

      (SELECT count(PIQG.APP_UID)
       FROM rp_workflow.PMT_INSP_QC_GRID PIQG
       JOIN rp_workflow.PMT_INSP_NORMAL PIN2 ON PIQG.APP_UID = PIN2.APP_UID
       AND PIN2.USR_UID_ORDER = wf_workflow.U.USR_UID
       WHERE PIN2.APP_STATUS = 'Completed') AS 'Total B'
    FROM wf_workflow.USERS U

Answer 1

尝试

SELECT username,
       SUM(CASE WHEN source = 1 THEN total END) total_a,
       SUM(CASE WHEN source = 2 THEN total END) total_b
  FROM
(
    SELECT 1 source,
           u.usr_username username,
           COUNT(pig.app_uid) total
      FROM rp_workflow.pmt_insp_grid pig JOIN rp_workflow.pmt_insp_normal pin
        ON pig.app_uid = pin.app_uid JOIN wf_workflow.users u
        ON pin.usr_uid_order = u.usr_uid
     GROUP BY u.usr_username
    UNION ALL
    SELECT 2 source,
           u.usr_username username,
           COUNT(piqg.app_uid) total
      FROM rp_workflow.pmt_insp_qc_grid piqg JOIN rp_workflow.pmt_insp_normal pin
        ON piqg.app_uid = pin.app_uid JOIN wf_workflow.users u
        ON pin.usr_uid_qc = u.usr_uid
      WHERE pin.app_status = 'Completed'
     GROUP BY u.usr_username
) q
GROUP BY username

MySQL多个数据库的多个查询

1 个答案: