oracle使用LEFT JOIN关联产生的问题在查询结果中使用CASE WHEN 无法判断

oracle使用LEFT JOIN关联产生的问题在查询结果中使用CASE WHEN 无法判断

查询方式一：

 SELECT
 CASE WHEN (SELECT CAST(SUM(CASE
 WHEN (ALLOCABLE_PRIME_CURRENCY_VALUE IS NULL AND STATE_IND = 1) THEN
 NVL(PRIME_CURRENCY_VALUE, 0)
 ELSE
 NVL(ALLOCABLE_PRIME_CURRENCY_VALUE, 0) END) AS NUMBER(18,6)) AS ALLOCABLE_PRIME_CURRENCY_VALUE
 FROM RP_LEDGER_ITEM R
 WHERE R.SOURCE_ID = RP_CASH_MOVEMENT.CASH_MOVEMENT_ID
 AND SOURCE_TYPE = 'CASH') = 0 THEN 0 ELSE 1 END,
 (SELECT SUM(CASE
 WHEN (ALLOCABLE_PRIME_CURRENCY_VALUE IS NULL AND STATE_IND = 1) THEN
 NVL(PRIME_CURRENCY_VALUE, 0)
 ELSE
 NVL(ALLOCABLE_PRIME_CURRENCY_VALUE, 0) END) AS ALLOCABLE_PRIME_CURRENCY_VALUE
 FROM RP_LEDGER_ITEM R
 WHERE R.SOURCE_ID = RP_CASH_MOVEMENT.CASH_MOVEMENT_ID
 AND SOURCE_TYPE = 'CASH'),
 RP_LEDGER_ITEM.LEDGER_ITEM_ID
 FROM RP_CASH_MOVEMENT
 LEFT JOIN RP_LEDGER_ITEM
 ON RP_LEDGER_ITEM.CASH_MOVEMENT_ID = RP_CASH_MOVEMENT.CASH_MOVEMENT_ID
 AND RP_LEDGER_ITEM.CASH_MOVEMENT_ID IS NOT NULL
 WHERE NVL(RP_CASH_MOVEMENT.IS_RESERVE_FUND, '') = ''
 AND 1 = 1
 AND RP_CASH_MOVEMENT.RP_ID = 'R'
 AND RP_CASH_MOVEMENT.INPUT_DATE >=
 TO_DATE('2014/2/1 0:00:00', 'YYYY-MM-DD HH24:MI:SS')
 AND (RP_CASH_MOVEMENT.OFFICE_ID = '0B4B12XOG33MO')

查询结果如下：

查询方式二：

SELECT
CASE WHEN (SELECT CAST(SUM(CASE
WHEN (ALLOCABLE_PRIME_CURRENCY_VALUE IS NULL AND STATE_IND = 1) THEN
NVL(PRIME_CURRENCY_VALUE, 0)
ELSE
NVL(ALLOCABLE_PRIME_CURRENCY_VALUE, 0) END) AS NUMBER(18,6)) AS ALLOCABLE_PRIME_CURRENCY_VALUE
FROM RP_LEDGER_ITEM R
WHERE R.SOURCE_ID = RP_CASH_MOVEMENT.CASH_MOVEMENT_ID
AND SOURCE_TYPE = 'CASH') = 0 THEN 0 ELSE 1 END,
(SELECT SUM(CASE
WHEN (ALLOCABLE_PRIME_CURRENCY_VALUE IS NULL AND STATE_IND = 1) THEN
NVL(PRIME_CURRENCY_VALUE, 0)
ELSE
NVL(ALLOCABLE_PRIME_CURRENCY_VALUE, 0) END) AS ALLOCABLE_PRIME_CURRENCY_VALUE
FROM RP_LEDGER_ITEM R
WHERE R.SOURCE_ID = RP_CASH_MOVEMENT.CASH_MOVEMENT_ID
AND SOURCE_TYPE = 'CASH'),
'' LEDGER_ITEM_ID
FROM RP_CASH_MOVEMENT
LEFT JOIN RP_LEDGER_ITEM
ON RP_LEDGER_ITEM.CASH_MOVEMENT_ID = RP_CASH_MOVEMENT.CASH_MOVEMENT_ID
AND RP_LEDGER_ITEM.CASH_MOVEMENT_ID IS NOT NULL
WHERE NVL(RP_CASH_MOVEMENT.IS_RESERVE_FUND, '') = ''
AND 1 = 1
AND RP_CASH_MOVEMENT.RP_ID = 'R'
AND RP_CASH_MOVEMENT.INPUT_DATE >=
TO_DATE('2014/2/1 0:00:00', 'YYYY-MM-DD HH24:MI:SS')
AND (RP_CASH_MOVEMENT.OFFICE_ID = '0B4B12XOG33MO')

查询结果如图：

2条sql语句最大的区别在于

有些可能表达不清楚，

主要原因我也不知道，如果谁有兴趣可以回复我！