关于索引不生效的问题

各位大虾们，小弟有个问题不解，望各位给点帮助

我在Table_name 表中建立索引
create index I_VEHICLEPASS_COM2 on Table_name (PASSTIME,crosslsh，PLATEINFO)
create bitmap index I_VEHICLEPASS_COM1 on Table_name (crosslsh);

select count(1)
  from TABLE_NAME v
  where passTime >=
  to_timestamp('2011-5-1 00:00:00', 'yyyy-mm-dd HH24:MI:SS')
  and passTime <=
  to_timestamp('2011-5-30 23:59:59', 'yyyy-mm-dd HH24:MI:SS')
  and CROSSLSH in (21)
  and plateInfo like '%'


1 Plan hash value: 939785991
2  
3 -----------------------------------------------------------------------------------------
4 | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
5 -----------------------------------------------------------------------------------------
6 | 0 | SELECT STATEMENT | | 1 | 23 | 26558 (2)| 00:05:19 |
7 | 1 | SORT AGGREGATE | | 1 | 23 | | |
8 |* 2 | FILTER | | | | | |
9 |* 3 | INDEX RANGE SCAN| I_VEHICLEPASS_COM2 | 293K| 6588K| 26558 (2)| 00:05:19 |
10 -----------------------------------------------------------------------------------------
11  
12 Predicate Information (identified by operation id):
13 ---------------------------------------------------
14  
15 2 - filter(TO_TIMESTAMP('2011-5-1 00:00:00',:B1)<=TO_TIMESTAMP('2011-5-30 
16 23:59:59',:B2))
17 3 - access("PASSTIME">=TO_TIMESTAMP('2011-5-1 00:00:00',:B1) AND 
18 "CROSSLSH"=21 AND "PASSTIME"<=TO_TIMESTAMP('2011-5-30 23:59:59',:B2))
19 filter("CROSSLSH"=21 AND "PLATEINFO" LIKE '%')


这里用来索引


但是我再加一个条件 就不用索引，而是进行全部扫描
select count(1)
  from TABLE_NAME v
  where passTime >=
  to_timestamp('2011-5-1 00:00:00', 'yyyy-mm-dd HH24:MI:SS')
  and passTime <=
  to_timestamp('2011-5-30 23:59:59', 'yyyy-mm-dd HH24:MI:SS')
  and CROSSLSH in (21)
  and plateInfo like '%'
  and drivewayNumber = '1'


1 Plan hash value: 477241886
2  
3 -------------------------------------------------------------------------------------------
4 | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
5 -------------------------------------------------------------------------------------------
6 | 0 | SELECT STATEMENT | | 1 | 26 | 205K (3)| 00:41:06 |
7 | 1 | SORT AGGREGATE | | 1 | 26 | | |
8 |* 2 | FILTER | | | | | |
9 |* 3 | TABLE ACCESS FULL| TABLE_NAME | 24445 | 620K| 205K (3)| 00:41:06 |
10 -------------------------------------------------------------------------------------------
11  
12 Predicate Information (identified by operation id):
13 ---------------------------------------------------
14  
15 2 - filter(TO_TIMESTAMP('2011-5-1 00:00:00',:B1)<=TO_TIMESTAMP('2011-5-30 
16 23:59:59',:B2))
17 3 - filter("CROSSLSH"=21 AND "DRIVEWAYNUMBER"=1 AND 
18 "PASSTIME"<=TO_TIMESTAMP('2011-5-30 23:59:59',:B1) AND 
19 "PASSTIME">=TO_TIMESTAMP('2011-5-1 00:00:00',:B2) AND "PLATEINFO" LIKE '%')

这是为什么呢？ 很困惑啊！ 望大虾赐教……！！！
谢谢！

兄弟，我也很好奇，建表语句和数据能不能共享一下？ 我想在我这边再现一下。