An issue with the left JOIN association that Oracle uses when using case in query results cannot be judged

An issue with the left JOIN association that Oracle uses when using case in query results cannot be judged

Query method One:

1 SELECT 2  Case  when(SELECT CAST(SUM( Case3  when(Allocable_prime_currency_value is NULL  andState_ind= 1) Then4NVL (Prime_currency_value,0)5 ELSE6NVL (Allocable_prime_currency_value,0)END) as  Number( -,6)) asAllocable_prime_currency_value7  fromRp_ledger_item R8 WHEREr.source_id=rp_cash_movement. cash_movement_id9  andSource_type= 'CASH')= 0  Then 0 ELSE 1 END,Ten(SELECT SUM( Case One  when(Allocable_prime_currency_value is NULL  andState_ind= 1) Then ANVL (Prime_currency_value,0) - ELSE -NVL (Allocable_prime_currency_value,0)END) asAllocable_prime_currency_value the  fromRp_ledger_item R - WHEREr.source_id=rp_cash_movement. cash_movement_id -  andSource_type= 'CASH'), - Rp_ledger_item. ledger_item_id +  fromrp_cash_movement -  Left JOINRp_ledger_item +  onRp_ledger_item. cash_movement_id=rp_cash_movement. cash_movement_id A  andRp_ledger_item. cash_movement_id is  not NULL at WHERENVL (Rp_cash_movement.is_reserve_fund,'0')= '0' -  and 1 = 1 -  andRp_cash_movement. rp_id= 'R' -  andRp_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')

The query results are as follows:

Query method Two:

SELECT  Case  when(SELECT CAST(SUM( Case when(Allocable_prime_currency_value is NULL  andState_ind= 1) ThenNVL (Prime_currency_value,0)ELSENVL (Allocable_prime_currency_value,0)END) as  Number( -,6)) asAllocable_prime_currency_value fromRp_ledger_item RWHEREr.source_id=rp_cash_movement. cash_movement_id andSource_type= 'CASH')= 0  Then 0 ELSE 1 END,(SELECT SUM( Case when(Allocable_prime_currency_value is NULL  andState_ind= 1) ThenNVL (Prime_currency_value,0)ELSENVL (Allocable_prime_currency_value,0)END) asAllocable_prime_currency_value fromRp_ledger_item RWHEREr.source_id=rp_cash_movement. cash_movement_id andSource_type= 'CASH'),"'ledger_item_id fromrp_cash_movement Left JOINRp_ledger_item onRp_ledger_item. cash_movement_id=rp_cash_movement. cash_movement_id andRp_ledger_item. cash_movement_id is  not NULLWHERENVL (Rp_cash_movement.is_reserve_fund,'0')= '0' and 1 = 1 andRp_cash_movement. rp_id= 'R' andRp_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')

Query results

The biggest difference between 2 SQL statements is that

Some may not express it clearly,

The main reason I do not know, if anyone interested can reply to me!