相关子查询的 SQL 问题

Question

我有这个 SQL 查询：

SELECT
  HALLS_REGISTRATION.ID,
  (
    CAST(
        (SELECT
           HALLS_REGISTRATION.MONEY_RECEIVED_NUMERIC
         FROM
           HALLS_REGISTRATION
         WHERE
           HALLS_REGISTRATION.ID = 2)
        AS DECIMAL
    )
    +
    (SELECT
       SUM(
           CAST(
               HALLS_REGISTRATION_PAID.PAID_MONEY
               AS DECIMAL
           )
       )
     FROM
       HALLS_REGISTRATION_PAID
     WHERE
       HALLS_REGISTRATION_PAID.REGISTRATION_ID = HALLS_REGISTRATION.ID
    )
  )
FROM HALLS_REGISTRATION;

这很好用，但这不是我想要的。我想要的是用从外部选择返回的HALLS_REGISTRATION.ID 替换第 10 行的2，所以当我尝试这种方法时，

SELECT
  HALLS_REGISTRATION.ID,
  (
    CAST(
        (SELECT
           HALLS_REGISTRATION.MONEY_RECEIVED_NUMERIC
         FROM
           HALLS_REGISTRATION
         WHERE
           HALLS_REGISTRATION.ID = ROOT.HALLS_REGISTRATION.ID)
        AS DECIMAL
    )
    +
    (SELECT
       SUM(
           CAST(
               HALLS_REGISTRATION_PAID.PAID_MONEY
               AS DECIMAL
           )
       )
     FROM
       HALLS_REGISTRATION_PAID
     WHERE
       HALLS_REGISTRATION_PAID.REGISTRATION_ID = HALLS_REGISTRATION.ID
    )
  )
FROM HALLS_REGISTRATION AS ROOT;

DataGrip 将 Root 视为未解析的符号，我在执行时收到此错误

[42S22][42122] 未找到列“HALLS_REGISTRATION.ID”； SQL 声明：

我希望查询与 H2、MySQL 或两者兼容。

Answer 1

这个：

SELECT
  HALLS_REGISTRATION.ID,
  (
    CAST(
        (SELECT
           HALLS_REGISTRATION.MONEY_RECEIVED_NUMERIC
         FROM
           HALLS_REGISTRATION, HALLS_REGISTRATION_PAID
         WHERE
           WHERE
       HALLS_REGISTRATION_PAID.REGISTRATION_ID = HALLS_REGISTRATION.ID)
        AS DECIMAL
    )
    +
    (SELECT
       SUM(
           CAST(
               HALLS_REGISTRATION_PAID.PAID_MONEY
               AS DECIMAL
           )
       )
     FROM
       HALLS_REGISTRATION_PAID
     WHERE
       HALLS_REGISTRATION_PAID.REGISTRATION_ID = HALLS_REGISTRATION.ID
    )
  )
FROM HALLS_REGISTRATION;

可能会做你想做的事。

Answer 2

错误消息不是关于ROOT，而是第二个子SELECT。

SELECT
  ROOT.ID,
  (
    CAST(
        (SELECT
           HALLS_REGISTRATION.MONEY_RECEIVED_NUMERIC
         FROM
           HALLS_REGISTRATION
         WHERE
           HALLS_REGISTRATION.ID = ROOT.ID)
        AS DECIMAL
    )
    +
    (SELECT
       SUM(
           CAST(
               PAID_MONEY
               AS DECIMAL
           )
       )
     FROM
       HALLS_REGISTRATION_PAID
     WHERE
       REGISTRATION_ID = ROOT.ID
    )
  )
FROM HALLS_REGISTRATION AS ROOT;

我不确定，您是否需要所有这些子查询...

试试这样的：

SELECT r.id, r.money_received_numeric + SUM(p.paid_money)
FROM halls_registration AS r
LEFT JOIN halls_registration_paid AS p ON r.id = p.registration_id
GROUP BY r.id;