SQL查询＆gt; sysdate <sysdate + =“”1 =“”year =“”

Question

=“”

我正在尝试编写一个查找最大到期时间的查询约会，但我注意到的是，当我这样做时，如果我有一个到期日期，我可以说没有结果，比如30-Dec-16，对于同一部分我也有一个到期日期为01-Jan-2099（这是默认的日期，如果没有填写）下面是我的查询我怎么能​​重写expiration_date查询以获得正确的日期。

SELECT 
 Part,
 price,
 effective_date,
 expiration_date
FROM a.Table 
 WHERE Part IN ('&Part') 
 AND PRICE  IN ('somewere') 
 AND expiration_date IN (SELECT 
                          MAX(expiration_date) 
                          FROM table  
                          WHERE expiration_date > SYSDATE 
                          AND  part IN ('&Part)  
                          AND PRICE IN (Somewere)) 
 AND to_date(effective_date) IN (SELECT 
                                  MAX(EFFECTIVE_DATE) FROM b.table  
                                  WHERE expiration_date > SYSDATE 
                                  AND  Part IN ('&Part)  
                                  AND price  IN (somewere) 
                                  AND EFFECTIVE_DATE < SYSDATE + 1)