條件是A,B兩表，A中有ID，同一ID有兩值，以它更新時間為區別，現在要取的是最新的ID那個值，并且關聯到B中的一屬性。SQL不太好，留在這里以后繼續學習
SELECT? Distinct tab1.CUSTOMER_ID, ACV.LAST_NAME,tab1.maxla
?? FROM AR_CONTACTS_V ACV,
??????? (SELECT RC.CUSTOMER_ID CUSTOMER_ID, MAX(ACV.LAST_UPDATE_DATE) MAXLA
?????????? FROM AR_CONTACTS_V ACV, RA_CUSTOMERS RC
????????? WHERE ACV.CUSTOMER_ID(+) = RC.CUSTOMER_ID
????????? GROUP BY RC.CUSTOMER_ID) TAB1
? WHERE ACV.CUSTOMER_ID(+) = TAB1.CUSTOMER_ID
??? AND ACV.LAST_UPDATE_DATE(+) = TAB1.MAXLA